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Effects of tree size and organ age on variations in carbon,nitrogen,and phosphorus stoichiometry in Pinus koraiensis

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Journal of Forestry Research 2024年第3期35卷 155-165页

作者： Yanjun Wang Guangze Jin zhili liu Center for Ecological Research Northeast Forestry UniversityHarbin 150040People's Republic of China Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education Northeast Forestry UniversityHarbin 150040People's Republic of China Northeast Asia Biodiversity Research Center Northeast Forestry UniversityHarbin 150040People's Republic of China

Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global ***,our knowledge of how these nutrients vary with tree size,organ age,or root order at the individual level remains *** determined C,N,and P contents and their stoichiometric ratios(i.e.,nutrient traits)in needles,branches,and fine roots at different organ ages(0-3-year-old needles and branches)and root orders(1st-4th order roots)from 64 Pinus koraiensis of varying size(Diameter at breast height ranged from 0.3 to 100 cm)in northeast *** factors were also *** results show that nutrient traits were regulated by tree size,organ age,or root order rather than soil *** a whole-plant level,nutrient traits decreased in needles and fine roots but increased in branches with tree *** the organ level,age or root order had a negative effect on C,N,and P and a positive effect on stoichiometric *** results demonstrate that nutrient variations are closely related to organ-specific functions and ecophysiological processes at an individual *** is suggested that the nutrient acquisition strategy by younger trees and organ fractions with higher nutrient content is for ***,nutrient storage strategy in older trees and organ fractions are mainly for steady *** results clarified the nutrient utilization strategies during tree and organ ontogeny and suggest that tree size and organ age or root order should be simultaneously considered to understand the complexities of nutrient variations.

关键词： Tree size Organ age(or root order) Carbon(C) Nitrogen(N) Phosphorus(P) Pinus koraiensis

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Effects of ontogenetic stage and leaf age on leaf functional traits and the relationships between traits in Pinus koraiensis

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Journal of Forestry Research 2021年第6期32卷 2459-2471页

作者： Meng Ji Guangze Jin zhili liu Center for Ecological Research Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management−Ministry of Education Northeast Forestry UniversityHarbin 150040People’s Republic of China

Investigating the effects of ontogenetic stage and leaf age on leaf traits is important for understanding the utilization and distribution of resources in the process of plant ***,few studies have been conducted to show how traits and trait-trait relationships change across a range of ontogenetic stage and leaf age for evergreen coniferous *** divided 67 Pinus koraiensis *** *** various sizes(0.3-100 cm diameter at breast height,DBH)into four ontogenetic stages,i.e.,young trees,middle-aged trees,mature trees and over-mature trees,and measured the leaf mass per area(LMA),leaf dry matter content(LDMC),and mass-based leaf nitrogen content(N)and phosphorus content(P)of each leaf age group for each sampled ***-way analysis of variance(ANOVA)was used to describe the variation in leaf traits by ontogenetic stage and leaf *** standardized major axis method was used to explore the effects of ontogenetic stage and leaf age on trait-trait *** found that LMA and LDMC increased significantly and N and P decreased significantly with increases in the ontogenetic stage and leaf *** trait-trait relationships were consistent with the leaf economic spectrum(LES)at a global *** them,leaf N content and LDMC showed a significant negative correlation,leaf N and P contents showed a significant positive correlation,and the absolute value of the slopes of the trait-trait relationships showed a gradually increasing trend with an increasing ontogenetic *** and LDMC showed a significant positive correlation,and the slopes of the trait-trait relationships showed a gradually decreasing trend with leaf ***,there were no significant relationships between leaf N content and LMA in most groups,which is contrary to the expectation of the ***,in the early ontogenetic stages and leaf ages,the leaf traits tend to be related to a"low investment-quick returns"resource *** contrast,in the late ontogenetic stages

关键词： Leaf age Leaf dry matter content Leaf mass per area Leaf nitrogen content Leaf phosphorus content Ontogenetic stage Pinus koraiensis

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Self-organizing feature map neural network classification of the ASTER data based on wavelet fusion

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Science China Earth Sciences 2004年第7期47卷 651-658页

作者： HASI Bagan MA Jianwen LI Qiqing HAN Xiuzhen liu zhili Laboratory of Remote Sensing Information Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Laboratory of Remote Sensing Information Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Laboratory of Remote Sensing Information Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Laboratory of Remote Sensing Information Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Laboratory of Remote Sensing Information Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China

Most methods for classification of remote sensing data are based on the statistical parameter evaluation with the assumption that the samples obey the normal distribution. How-ever, more accurate classification results can be obtained with the neural network method through getting knowledge from environments and adjusting the parameter (or weight) step by step by a specific measurement. This paper focuses on the double-layer structured Kohonen self-organizing feature map (SOFM), for which all neurons within the two layers are linked one another and those of the competition layers are linked as well along the sides. Therefore, the self-adapting learning ability is improved due to the effective competition and suppression in this method. The SOFM has become a hot topic in the research area of remote sensing data classi-fication. The Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER) is a new satellite-borne remote sensing instrument with three 15-m resolution bands and three 30-m resolution bands at the near infrared. The ASTER data of Dagang district, Tianjin Munici-pality is used as the test data in this study. At first, the wavelet fusion is carried out to make the spatial resolutions of the ASTER data identical; then, the SOFM method is applied to classifying the land cover types. The classification results are compared with those of the maximum likeli-hood method (MLH). As a consequence, the classification accuracy of SOFM increases about by 7% in general and, in particular, it is almost as twice as that of the MLH method in the town.

关键词： classification, wavelet fusion, self-organizing neural network feature map (SOFM), ASTER data.

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Assessing the relative role of climate change and human activities in sandy desertification of Ordos region, China

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Science China Earth Sciences 2009年第6期52卷 855-868页

作者： XU DuanYang KANG XiangWu liu zhili ZHUANG DaFang PAN JianJun College of Resource and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095China Institute of Scientific and Technical Information of China Beijing 100038China The National Meteorological Center Beijing 100081China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Climate change and human activities are driving forces of sandy desertification and the relative role of them in sandy desertification is the hot point in related researches. A study was carried to assess the relative role of climate change and human activities in sandy desertification of Ordos region in China. Potential NPP and the difference between potential and actual NPP were selected as indicators to assess the relative role of climate change and human activities in sandy desertification, respectively. Assessing methods were built based on some scenarios for the reversion and expansion of sandy desertification and the relative role of climate change and human activities in sandy desertification of Ordos region were assessed from 1981 to 2000. The results showed that although some local places experienced an expansion of sandy desertification, the change of sandy desertification of Ordos region from 1981 to 2000 showed a stably reversing trend. The relative role of climate change and human activities in sandy desertification of Ordos region varied at different temporal and spatial scales in the reversion and expansion processes. In the reversion of sandy desertification, climate change was the dominant factor in the period of 1981 to 1990 and the reversed areas mainly induced by climate change including Mu Us sandy land and the transition zone between temperate steppe and temperate deciduous scrubs in north east of Ordos region; however, human activities controlled the reversed process during the period from 1991 to 2000 and the areas mainly induced by human activities distributed in all banners of Ordos region. In the expansion of sandy desertification, human activities were the dominant factor in the period of 1981 to 1990 and the expanded areas mainly included the regions around common boundary of Hanggin, Dalad Banners and Dongsheng City; however, climate change dominated the expansion of sandy desertification from 1991 to 2000, the expanded areas equably d

关键词： Ordos causes of sandy desertification climate change human activities relative role NPP

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Leaf nitrogen resorption is more important than litter nitrogen mineralization in mediating the diversity–productivity relationship along a nitrogen-limited temperate forest succession chronosequence

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Forest Ecosystems 2023年第1期10卷 132-140页

作者： Peng Zhang Xiao-Tao Lü Guangze Jin zhili liu Mai-He Li Center for Ecological Research Northeast Forestry UniversityHarbin150040China Forest Dynamics Swiss Federal Institute for ForestSnow and Landscape Research WSLCH-8903BirmensdorfSwitzerland Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang110016China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin150040China Northeast Asia Biodiversity Research Center Northeast Forestry UniversityHarbin150040China Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China School of Life Science Hebei UniversityBaoding071000China

The resorption of nutrients by plants before litter fall and the mineralization of nutrients from plant litter by soil processes are both important pathways supporting primary productivity. While the positive relationship between plant biodiversity and primary productivity is widely accepted for natural ecosystems, the roles of nutrient resorption and mineralization in mediating that relationship remains largely unknown. Here, we quantified the relative importance of nitrogen(N) resorption and N mineralization in driving plant community N investment and the correlation between species diversity and community productivity along an N-limited successional chronosequence of the mixed broadleaved–Korean pine(Pinus koraiensis) forest in northeastern China. Leaf N resorption efficiency(NRE) at the community level increased significantly along the successional chronosequence,whereas litter N mineralization rate decreased significantly. Leaf NRE was more important than litter N mineralization rate in driving the diversity–productivity relationship. However, higher leaf NRE led to less N mineralization as succession progressed along the chronosequence. Our results highlight the importance of the N resorption pathway rather than the N mineralization pathway for forest N acquisition with community succession,and they provide mechanistic insights into the positive effects of biodiversity on ecosystem functioning. In future forest management practices, we recommend appropriate application of N fertilizer to mitigate the adverse effects of N-poor soil on seedling regeneration during late succession and thus maintain the sustainable development of temperate forest ecosystems.

关键词： Community composition Diversity Ecosystem functioning N cycling N limited Niche complementarity Trade-off

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Distribution of aromatic bio-markers in pyrolysates of co-ccolithophore

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Chinese Science Bulletin 2001年第3期46卷 246-252页

作者： ZHOU Wen WU Qingyu WANG Ruiyong SONG Yitao ZHANG Linye liu zhili Department of Biological Science and Technology Nanjing UniversityNanjing 210093China Department of Biological Science and Technology Tsinghua UniversityBeijing 100084China Geological Science and Research Institute Shengli Petroleum Administration BureauDongying 257015China

Analyses of the original and pyrolytic products of coccolithophore at various temperatures suggest that the contribution of coccolithophore to the formation of large immature oil reservoirs should attract keen interest. Through biochemical processes algae can change inorganic sulphur into organic sulphur, which could be one of the most important precursors of organic sulphur compounds in oil and source rocks. When Methylphenanthrene Index (MPI) and Methylphenanthrene Ratio (MPR) indices were used to evaluate the evolution degree of source rocks and oil maturity, other maturity indices must be used together for correction. In low maturity, the relative abundances of diben-zothiophene (DBT), fluorine (F) and dibenzofuran (DBF) can be used to identify the oxidation-reduction environments.

关键词： coccolithophore pyrolysates aromatic biomarkers.

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Research on the quality deterioration of UHT milk products during shelf life:core microorganisms and related characteristics

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Food Science and Human Wellness 2024年第5期13卷 2866-2875页

作者： Ruixue Ding Kairu He Rina Wu Mengxue Lou zhili liu Yuqiong Piao Xiaoyan liu Zhishen Mu Junrui Wu College of Food Science Shenyang Agricultural UniversityShenyang 110866China Shenyang Key Laboratory of Microbial Fermentation Technology Innovation Shenyang 110866China Liaoning Engineering Research Center of Food Fermentation Technology Shenyang 110866China Inner Mongolia Mengniu Dairy Grp.Co. Ltd.Hohhot 010000China

Commercial sterility does not guarantee the sustained stability of ultrahigh temperature(UHT)milk over 6 months shelf *** explore the microbiota presented in normal(SZ)and quality deteriorated UHT milk(QY and WY)products from the same *** on high-throughput sequencing research results,11 phyla and 54 genera were identified as dominant ***,Streptococcus,and Acinetobacter as core functional microbiota significantly influenced the UHT milk quality ***,principal component analysis(PCA)and multivariate analyses were used to examine the quality characteristics,including 11 physicochemical parameters,10 fatty acids,and 2 enzyme activities,in normal and quality deteriorated UHT *** found that the abundance of Pseudomonas increased in quality deteriorated milk(WY)and showed a significant positive correlation with heat-resistant protease *** in quality deteriorated milk(QY)also considerably contributed to the content of heat-resistant lipase,which resulted in spoilage deterioration of UHT milk.

关键词： Ultrahigh temperature(UHT) Quality deterioration High-throughput sequencing Core functional microbiota Lipase Protease

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A Simulated Test of Algal Influence of Formation and Deposition of Phosphates

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 417-426页

作者： liu zhili liu Xuexian Fan Yigong Zhu Shixin Department of Biology, Nanjing University Tianjin Institute of Geology and Mineral Resources,Chinese Academy of Geological Sciences Department of Biology Nan jing University China

This paper deals with a simulated test of biogenic mineralization made with a blue-green alga species,Spirulina platensix. The data in the experiment were recorded by a computerized surveying system. The influ-ence of algae on the accumulation of phosphorus by changing their microenvironment to promote the forma-tion and deposition of phosphate was studied. The results show that the pH value of cultural liquor rose up to 10 and the redox potential (Eh) may dropby 100-200 mV during the algal logarithmic growth stage, and the cultrual liquor was changed into a mediumwith a weakly reducing condition. At the end of the logarithmic growth stage white deposits of Na_2Ca(CO_3)_2·5H_2O and Ca_2Mg (PO_4)_2·2H_2O were formed on the floor of cultural containers. The test presented a wduableevidence for the theory of biogenic mineralization.

关键词： In A Simulated Test of Algal Influence of Formation and Deposition of Phosphates Test

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Biogeochemical Model and Simulation of the Effect of Precambrian Algae on the Formation Process of Certain Laminated Cherts

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Acta Geologica Sinica(English Edition) 1986年第4期60卷 67-81+101-102页

作者： Wu Qingyu, liu zhili and Zhu Haoran Department of Biology, Nanjing University, Nanjing, Jiangsu Department of Biology Nanjing University Nanjing Jiangsu

The source of silica in the formation of the Precambrian laminated cherts has long remained a problem to be solved. Through experiments on cherts and living blue-green algae, the authors found that the collected chert samples probably come from primary deposits, and there is a great biomass of fossil algae in chert, among which the filamentous algae can be compared with the living blue-green algae Oscillatoria, that a higher Pco;of the gas would be favourable for the increase of the biomass of living blue-green algae and consequently raises the pH value of the water body; and that lack of free oxygen and a higher concentration of SiO;in the water have no apparent influence on the biomass of blue-green algae. Based on the evidence above, a biogeochemical model concerning the origin of Precambrian laminated chert has been set up, in which the. photosynthesis of algae under the presumed atmospheric conditions of the Precambrian might raise the pH value of the water body and promote the dissolution of silicate minerals, thus providing a source of colloid SiO;for the formation of Precambrian laminated ***, a simulation experiment device has been designed successfully, which can control the temperature（30 ± 0.5°）, Pco;（50662.5 Pa） and Po;（about zero Pa） of the gas, the rate of photosynthesis of algae and the movement of the water carrying opal. In the simulation experiments, separate measurements have been made on the rate of photosynthesis of algae, pH value and concentration of SiO;of the water body, with the results indicating that under the conditions similar to the presumed Precambrian atmosphere, the photosynthesis of algae can make the pH value of the water body go up steadily to over 9.7, leading to the dissolution of the silicate minerals, with the concentration of SiO;measured reaching as high as 84 mg/l. Finally, through the vaporation of water, a phenomenon of colloid floccilation has been *** simulation experiment has verified the propo

关键词： Biogeochemical Model and Simulation of the Effect of Precambrian Algae on the Formation Process of Certain Laminated Cherts Simulation

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Plasma Extracellular Vesicle MicroRNA Analysis of Alzheimer’s Disease Reveals Dysfunction of a Neural Correlation Network

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Research 2023年第4期2023卷 689-699页

作者： Yuzhe Sun Zhen Hefu Benchao Li Wang Lifang Song Zhijie Li Zhou Yan Deng liu zhili Jiahong Ding Tao Li Wenwei Zhang Nie Chao Shuang Rong Department of Nutrition and Food Hygiene School of Public HealthMedical CollegeWuhan University of Science and TechnologyWuhanChina BGI-Shenzhen ShenzhenChina Shenzhen Key Laboratory of Neurogenomics BGI-ShenzhenShenzhen 518120China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China.

Small extracellular vesicle(sEV)is an emerging source of potential biomarkers of Alzheimer's disease(AD),but the role of microRNAs(miRNAs)in sEV is not well *** this study,we conducted a comprehensive analysis of sEV-derived miRNAs in AD using small RNA sequencing and coexpression network *** examined a total of 158 samples,including 48 from AD patients,48 from patients with mild cognitive impairment(MCI),and 62 from healthy *** identified an miRNA network module(M1)that was strongly linked to neural function and showed the strongest association with AD diagnosis and cognitive *** expression of miRNAs in the module was decreased in both AD and MCI patients compared to *** analysis revealed that M1 was highly preserved in the healthy control group but dysfunctional in the AD and MCI groups,suggesting that changes in the expression of miRNAs in this module may be an early response to cognitive decline prior to the appearance of AD *** further validated the expression levels of the hub miRNAs in M1 in an independent *** functional enrichment analysis showed that 4 hub miRNAs might interact with a GDF11-centered network and play a critical role in the neuropathology of *** summary,our study provides new insights into the role of sEV-derived miRNAs in AD and suggests that M1 miRNAs may serve as potential biomarkers for the early diagnosis and monitoring of AD.

关键词： network analysis. diagnosis

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