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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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氮沉降对半干旱草原植物群落钙浓度的影响

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Journal of Plant Ecology 2022年第2期15卷 286-293页

作者： Shuang-li Hou xiao-tao lü Jun-Jie Yang Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China State Key laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

钙(Ca)是植物生长所必需的营养物质,牧草中钙的含量对反刍动物的饲粮和健康具有重要意义。目前,关于氮沉降增加是否改变牧草的Ca浓度仍不是十分清楚。我们于2008–2015年在中国北方半干旱草原开展了氮沉降速率增加实验,测定了不同氮处... 详细信息

钙(Ca)是植物生长所必需的营养物质,牧草中钙的含量对反刍动物的饲粮和健康具有重要意义。目前,关于氮沉降增加是否改变牧草的Ca浓度仍不是十分清楚。我们于2008–2015年在中国北方半干旱草原开展了氮沉降速率增加实验,测定了不同氮处理下每个样方内所有植物的Ca浓度,并且根据各样方内每个物种的Ca浓度及其相对生物量,计算出功能群水平和群落水平的植物Ca浓度。研究结果表明,尽管物种水平和功能群水平的Ca浓度对氮沉降表现为负响应,但群落水平Ca浓度在整个氮添加速率梯度上保持稳定。由于杂类草Ca浓度显著高于禾草,杂类草相对生物量的增加抵消了物种水平和功能群水平Ca浓度对氮沉降的负响应。另外,群落Ca库对氮添加速率表现为正饱和响应,且阈值为10 g N m^(−2)yr^(−1)。本研究表明了氮沉降背景下植物相对生物量的变化对调控牧草Ca浓度和储量具有重要作用。

关键词：钙储量群落组成生态过程全球变化氮沉降温带草原

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Mowing weakens the positive effects of nitrogen deposition on fundamental ecosystem service of grassland

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Ecological Processes 2021年第1期10卷 58-68页

作者： Cong Ding Guo-Jiao Yang xiao-Guang Wang Zi-Jia Zhang Yan-Yu Hu Zhi-Wei Zhang Shuang-li Hou xiao-tao lü Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China. University of Chinese Academy of Sciences Beijing 100049China Institute of Ecology and Biodiversity School of Life ScienceShandong UniversityQingdao 266237China. College of Environmental and Resource Sciences Dalian Minzu UniversityDalian 116600China.

Forage yield is the fundamental ecosystem service of grasslands.While the quantitative responses of forage yield to nitrogen(N)enrichment are well known,its qualitative responses remain unclear.Even less known is the relative contribution of changes in community composition to the quality of the yield at the community level.We examined the quantitative and qualitative responses of forage yield at both plant functional group and community levels with factorial treatments of N addition and mowing in a temperate steppe.Nitrogen addition significantly enhanced the community-level yield by favoring the growth of rhizomatous grass.Mowing tended to mediate the impacts of N addition on the yield.Nitrogen addition increased the concentrations of crude protein and crude fat in forage at the community level.Neither the main effects of mowing nor its interactive effects with N addition affected forage quality.The N-induced shifts in plant species composition significantly contributed to the effects of N addition on forage quality at the community level.Our results suggest that mowing wound weaken the positive effects of N deposition on the quantity but not the quality of forage yield.Changes in plant community composition are important in driving the qualitative responses of yield to N deposition.

关键词： Nitrogen enrichment Primary productivity Forage quality Forage yield Semi-arid grassland

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Opposite effects of nitrogen fertilization and plastic film mulching on crop N and P stoichiometry in a temperate agroecosystem

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Journal of Plant Ecology 2019年第4期12卷 682-692页

作者： Fan Ding Shuangyi li xiao-tao lü Feike A.Dijkstra Sean Schaeffer Tingting An Jiubo Pei liangjie Sun Jingkuan Wang College of land and Environment Shenyang Agricultural UniversityShenyang 110086China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China Sydney Institute of Agriculture School of Life and Environmental SciencesThe University of SydneyEveleighNSW 2015Australia Department of Biosystems Engineering and Soil Science University of TennesseeKnoxvilleTN 37996USA

Aims Crop nitrogen(N)and phosphorus(P)stoichiometry can influence food nutritive quality and many ecosystem processes.However,how and why N and P stoichiometry respond to long-term agricul-tural management practices(e.g.N fertilization and film mulching)are not clearly understood.Methods We collected maize tissues(leaf,stem,root and seed)and soil sam-ples from a temperate cropland under 30-year continuous N fer-tilization and plastic film mulching treatments,measured their C,N and P concentrations(the proportion(%)relative to the sample mass),and used structural equation models to uncover the re-sponding mechanisms for crop N and P contents(the total amount(g/m2)in crop biomass).Important Findings long-term N fertilization increased N concentrations in all crop tissues but sharply decreased P concentrations in vegetative tis-sues(leaf,stem and root),thereby reducing their C/N ratio and increasing C/P and N/P ratios.The drop in P concentration in vegetative tissues was due to the dilution effect by biomass in-crement and the priority of P supply for seed production.In con-trast,film mulching decreased N concentration but increased P concentrations in most crop tissues,thereby increasing C/N ratio and reducing C/P and N/P ratios.Film mulching increased crop P content by increasing soil temperature and moisture;whereas,mulching showed little effect on crop N content,because a posi-tive effects of soil temperature may have canceled out a negative effect by soil moisture.This indicated a decoupling of P and N uptake by crops under film mulching.In conclusion,N fertiliza-tion and plastic film mulching showed opposite effects of on crop N and P stoichiometry.

关键词： long-term soil stoichiometry soil moisture dilution effect maize tissues

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linking changes of forage production and digestibility with grassland community assembly under nitrogen enrichment

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Ecological Processes 2021年第1期10卷 441-448页

作者： xiao-tao lü Zhuo-Yi liu Seeta Sistla Guo-Jiao Yang Yan-Yu Hu Zhi-Wei Zhang Shuang-li Hou Cong Ding Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China Natural Resources Management and Environmental Sciences California Polytechnic State UniversitySan Luis ObispoCA 93407USA Institute of Ecology and Biodiversity School of Life ScienceShandong UniversityQingdao 266237China.

Background:Forage production is the fundamental ecosystem service of grasslands.Although forage consumption occurs at community level,most studies focused on species-level changes of forage quality.The quantitative and qualitative changes of forage production are driven by species-specific trait,intra-specific plasticity,and species turnover.We examined the changes in forage production and digestibility after 5-year factorial treatments of nitrogen(N)addition and mowing in a temperate steppe and linked such changes to community assembly under the Price equation framework.Results:Nitrogen addition significantly reduced species richness,increased forage production,but did not change forage digestibility(indicated by the total Ca+Mg concentrations).Mowing did not affect forage production and digestibility.The positive effects of N addition on forage production were driven by the enhancement of abundance of the remaining species following N enrichment,rather than by species loss or species gain.The species identity effects could offset the effects of species richness loss or gain on forage production and digestibility.Conclusions:Our results highlight the importance of a community perspective in addressing the quantitative and qualitative changes of forage production under global change pressure of N enrichment.Species identity is important in determining the contribution of different processes of community assembly to ecosystem services.

关键词： Community composition Nitrogen deposition Species turnover Price equation Primary productivity

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刈割能够缓解历史氮沉降对草地群落养分利用效率的负面影响

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Journal of Plant Ecology 2021年第5期14卷 959-969页

作者： Yan-Yu Hu Zhi-Wei Zhang Shuang-li Hou Jun-Jie Yang xiao-tao lü Erguna Forest-Steppe Ecotonc Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China State Key laboratory of Vegetation of Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

氮沉降的增加对草地生态系统结构和功能造成了诸多负面影响,包括改变植物群落结构和降低植物养分利用效率。许多国家的减排政策有效地减少了氮排放、降低了氮沉降速率,但历史氮沉降对生态系统的影响可能具有遗留效应。草地植物群落的养... 详细信息

氮沉降的增加对草地生态系统结构和功能造成了诸多负面影响,包括改变植物群落结构和降低植物养分利用效率。许多国家的减排政策有效地减少了氮排放、降低了氮沉降速率,但历史氮沉降对生态系统的影响可能具有遗留效应。草地植物群落的养分利用效率在氮沉降减少或者停止后作出何种响应,还有待于研究。作为草地重要的管理方式之一,刈割将如何调控历史氮沉降对植物养分利用效率的影响仍然属于知识空白。本研究探讨了氮素添加停止以后连续3年内功能群水平和群落水平上植物的氮、磷利用效率对历史氮素添加和刈割处理的响应。研究结果表明,历史氮素添加显著降低了植物功能群水平的氮利用效率,但未改变其磷利用效率;在群落水平上,历史氮素添加显著降低了植物的氮磷利用效率。刈割能够缓解历史氮素添加对植物群落氮磷利用效率的降低作用,该作用主要是抑制具有较低养分利用效率的根茎型高禾草的生长而促进具有较高养分利用效率的丛生型高禾草的生长。研究结果揭示了植物群落结构在驱动植物群落养分利用效率变化中的重要作用。本研究认为适当的草地管理方式有助于氮沉降过后草地植物养分利用效率的恢复。

关键词：群落结构刈割遗留效应养分利用植物功能群半干旱草原

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Control of fine particulate nitrate during severe winter haze in“2+26”cities

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Journal of Environmental Sciences 2024年第2期136卷 261-269页

作者： Chuang Qin xiao Fu tao Wang Jian Gao Jiaqi Wang Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Department of Civil and Environmental Engineering Hong Kong Polytechnic UniversityHong Kong 99907China State Key laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 10084China

The“2+26”cities,suffering the most severe winter haze pollution,have been the key region for air quality improvement in China.Increasing prominent nitrate pollution is one of the most challenging environmental issues in this region,necessitating development of an effective control strategy.Herein,we use observations,and state-of-the-art model simulations with scenario analysis and process analysis to quantify the effectiveness of the future SO_(2)-NO_(X)-VOC-NH_(3) emission control on nitrate pollution mitigation in“2+26”cities.Focusing on a serious winter haze episode,we find that limited NO_(X)emission reduction alone in the short-term period is a less effective choice than VOC or NH_3emission reduction alone to decrease nitrate concentrations,due to the accelerated NO_(X)-HNO_(3)conversion by atmospheric oxidants and the enhanced HNO_(3)to NO_(3)^(-)partition by ammonia,although deep NO_(X)emission reduction is essential in the long-term period.The synergistic NH_(3) and VOC emission control is strongly recommended,which can counteract the adverse effects of nonlinear photochemistry and aerosol chemical feedback to decrease nitrate more.Such extra benefits will be reduced if the synergistic NH_(3) and VOC reduction is delayed,and thus reducing emission of multiple precursors is urgently required for the effective control of increasingly severe winter nitrate pollution in“2+26”cities.

关键词： Nitrate Winter haze pollution Emission reduction “2+26”cities

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Analysis of the impact of immunotherapy efficacy and safety in patients with gastric cancer and liver metastasis

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 700-709页

作者： Kai liu Chun-xiao Wu Hui liang tao Wang Ji-Yuan Zhang xiao-tao Wang Department of Radiation and Oncology Traditional Chinese Hospital of Lu’an affiliated to Anhui University of Traditional Chinese MedicineLu’an 237000Anhui ProvinceChina Department of Gastroenterology Ehu branch of Xishan People’s Hospital of Wuxi CityWuxi 214116Jiangsu ProvinceChina Department of Gastrointestinal Surgery The First Affiliated Hospital of Guangzhou University of Traditional Chinese MedicineGuangzhou 510400Guangdong ProvinceChina Department of Gastrointestinal Surgery Hunan Provincial People’s HospitalChangsha 410002Hunan ProvinceChina Department of Traditional Chinese medicine Ehu branch of Xishan People’s Hospital of Wuxi CityWuxi 214116Jiangsu ProvinceChina

BACKGROUND Gastric cancer(GC)is the fifth most common type of cancer and has the fourth highest death rate among all cancers.There is a lack of studies examining the impact of liver metastases on the effectiveness of immunotherapy in individuals diagnosed with GC.AIM To investigate the influence of liver metastases on the effectiveness and safety of immunotherapy in patients with advanced GC.METHODS This retrospective investigation collected clinical data of patients with advanced stomach cancer who had immunotherapy at our hospital from February 2021 to January 2023.The baseline attributes were compared using either the Chi-square test or the Fisher exact probability method.The chi-square test and Kaplan-Meier survival analysis were employed to assess the therapeutic efficacy and survival duration in GC patients with and without liver metastases.RESUlTS The analysis comprised 48 patients diagnosed with advanced GC,who were categorized into two groups:A liver metastasis cohort(n=20)and a non-liver metastatic cohort(n=28).Patients with liver metastasis exhibited a more deteriorated physical condition compared to those without liver metastasis.The objective response rates in the cohort with metastasis and the cohort without metastasis were 15.0%and 35.7%(P>0.05),respectively.Similarly,the disease control rates in these two cohorts were 65.0%and 82.1%(P>0.05),respectively.The median progression-free survival was 5.0 months in one group and 11.2 months in the other group,with a hazard ratio of 0.40 and a significance level(P)less than 0.05.The median overall survival was 12.0 months in one group and 19.0 months in the other group,with a significance level(P)greater than 0.05.CONClUSION Immunotherapy is less effective in GC patients with liver metastases compared to those without liver metastasis.

关键词： Gastric cancer Spread of cancer to the liver Treatment with immunotherapy Effectiveness of treatment

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Toeplitz Operators and Carleson Measures for Weighted Bergman Spaces Induced by Regular Weights

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1345-1359页

作者： Jun tao DU Song xiao Hasi WUlAN Department of Mathematics Guangdong University of Petrochemical TechnologyMaoming 525000P.R.China Department of Mathematics Shantou UniversityShantou 515063P.R.China

In this paper,we give a universal description of the boundedness and compactness of Toeplitz operator T_(μ)^(ω)between Bergman spaces A_(η)^(p)and A_(υ)^(q)whenμis a positive Borel measure,1lar weights.By using Khinchin’s inequality and Kahane’s inequality,we get a new characterization of the Carleson measure for Bergman spaces induced by regular weights.

关键词： Bergman space Carleson measure Toeplitz operator regular weight

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Knowledge Graph Enhanced Transformers for Diagnosis Generation of Chinese Medicine

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Chinese Journal of Integrative Medicine 2024年第3期30卷 267-276页

作者： WANG Xin-yu YANG tao GAO xiao-yuan HU Kong-fa School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing210023China School of Information Management Nanjing UniversityNanjing210023China Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor Nanjing210023China Jiangsu Province Engineering Research Center of TCM Intelligence Health Service Nanjing210023China

Chinese medicine(CM)diagnosis intellectualization is one of the hotspots in the research of CM modernization.The traditional CM intelligent diagnosis models transform the CM diagnosis issues into classification issues,however,it is difficult to solve the problems such as excessive or similar categories.With the development of natural language processing techniques,text generation technique has become increasingly mature.In this study,we aimed to establish the CM diagnosis generation model by transforming the CM diagnosis issues into text generation issues.The semantic context characteristic learning capacity was enhanced referring to Bidirectional long Short-Term Memory(BIlSTM)with Transformer as the backbone network.Meanwhile,the CM diagnosis generation model Knowledge Graph Enhanced Transformer(KGET)was established by introducing the knowledge in medical field to enhance the inferential capability.The KGET model was established based on 566 CM case texts,and was compared with the classic text generation models including long Short-Term Memory sequence-to-sequence(lSTM-seq2seq),Bidirectional and Auto-Regression Transformer(BART),and Chinese Pre-trained Unbalanced Transformer(CPT),so as to analyze the model manifestations.Finally,the ablation experiments were performed to explore the influence of the optimized part on the KGET model.The results of Bilingual Evaluation Understudy(BlEU),Recall-Oriented Understudy for Gisting Evaluation 1(ROUGE1),ROUGE2 and Edit distance of KGET model were 45.85,73.93,54.59 and 7.12,respectively in this study.Compared with lSTM-seq2seq,BART and CPT models,the KGET model was higher in BlEU,ROUGE1 and ROUGE2 by 6.00–17.09,1.65–9.39 and 0.51–17.62,respectively,and lower in Edit distance by 0.47–3.21.The ablation experiment results revealed that introduction of BIlSTM model and prior knowledge could significantly increase the model performance.Additionally,the manual assessment indicated that the CM diagnosis results of the KGET model used in this study were highly consistent with the p

关键词： Chinese medicine diagnosis knowledge graph enhanced transformer text generation

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