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Journal of Environmental sciences 1998年第2期10卷 83-88页

作者： wu gang department of systems ecology, research Center for {2. Environmental sciences,{4., beijing 100085, china department of systems {2. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

In accordance with principles and methods of ecology, the effects of acidic deposition on productivity and volume increment of masson pine and Cinnamomum campora forest which are widely distributed in southern suburbs of Chongqing, china were studied. Based on the field data and measurements, a multivariable stepwise regression model was established to analyze the effects of multiple environmental factors on the productivity of the forest {2.systems. This model was used to assess the volume and {2.nomic losses of these two forest {2.systems caused by acidic deposition. The result showed that, among the environmental factors, pH value of precipitation, soil depth, soil organic contents and slope are the dominant ones influencing the growth of masson pine forest. It was also shown that the acidic deposition has no clear relation to the growth of *** forest, so development of such broad leaved forest is suitable in the area.

关键词： acidic deposition productivity volume increment economic loss.

Exploiting pattern and sustainable development of marginal lands in the Three Gorge Reservoir Areas

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Journal of Environmental sciences 2001年第2期13卷 173-179页

作者： wu gang, LI Jing, KONG Hong mei, ZHAO Jing zhu, GAO Lin ({2. of ecology System, {4. Center for eco Environmental sciences, chinese academy of sciences, beijing 100085, china) department of ecology System Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

This paper studied the distribution and utilization status, reasonable exploitation patterns and potential productivity, and sustainable development of marginal lands in the Three Gorge Reservoir Areas. It has been pointed that problems of the soil fertility degradation, poor productivity in crop lands, natural disasters and environmental deterioration existed in all the exploited marginal lands. In order to maintain the sustainability of the marginal lands, following measure have been proposed: prohibiting cultivation in the crop lands with a slope more than 2.°, restoring vegetation in the slope more than 2.°, strengthening the basic agricultural construction, establishing the production base of woody feeds and oils, establishing a multi dimensional management model with reasonable structure and optimum function for forestry, agriculture and fishing.

关键词： marginal lands utilization pattern sustainable development Three Gorge Reservoir Are4

Nitrogen, phosphorus and potassium recycling in an agroforestry ecosystem of Huanghuaihai Plain: with Paulownia elongata intercropped wheat and maize as an example

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Journal of Environmental sciences 1998年第2期10卷 62-69页

作者： wu gang department of systems ecology,research Center for {2. Environmental sciences,{4.,beijing 100085,china

The studies show that in the whole community, P is deficient, and N and K are basically balanced. N, P and K are accumulated in plant tissues and litters, but depleted in soil. N and P contents in surface soil(0—2. cm) are the main factors affecting crop growth, and P contents in 2. 80 cm soil layer is the major affecting Paulownia elongata growth. The absorption coefficients of N, P and K in the communities are 0 078, 0 014.and 0 052.respectively, their utilization coefficients are 0 95, 0 90 and 0 94. and the recycling coefficients are 0 04.0} 0 05 and 0 063 respectively.

关键词： nitrogen phosphorus, potassium recycling agroforestry ecosystem.

Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science china(Technological sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, wu gang, XU Dong, WANG Shunzhong &WANG Hui Institute of Applied {2., chinese academy of sciences, Shenyang 110016,{4. School of Forestry, Northeast Forestry University, Harbin 15004.,{4. State Key Lab of systems {2., research Center for eco-Environmental sciences, chinese academy of sciences,{12.,{4. Graduate University of chinese academy of sciences, beijing 100039,{4. 1. Institute of Applied ecology Chinese Academy of Sciences Shenyang 110016 China 2. School of Forestry Northeast Forestry University Harbin 150040 China 3. State Key Lab of systems ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. Graduate University of chinese academy of sciences Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was4..2., much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

Energy of forest systems in the Three Gorge Reservoir area

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Journal of Environmental sciences 1999年第1期11卷 110-114页

作者： wu gang, Su Rui ping {2. of systems {4., research Center for eco Environmental sciences, chinese academy of sciences, beijing 100085, china

The energies of three forest ecosystems in the Three Gorge Reservoir area were analyzed. The results showed that the existing energies were 151 2.38, 139 2.14.and 175 1659 (×10 10 J/hm 2., the annual net fixed energies were 38 892., 31 2.14.and 4. 82.1 (×10 10 J/hm 2., and the utilization efficiency of light energies were 1 16, 0 99 and 1 4. for the Quercus acutissima forest(Q.A.), the Pinus massoniana forest (P.M.), and the Queresus acutissima and Pinus massoniana mixed forest (Q.P.), respectively. In the Three Gorge Reservoir Area, the energy efficiency of Quercus acutissima and Pinus massoniana mixed forest is the best.

关键词： forest ecosystem energy Three Gorge Reservoir area.

Nutrient cycling characteristics of Quercus acutissima and Pinus massoniana mixed forest in the Three Gorge Reservoir area, china

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Journal of Environmental sciences 1998年第3期10卷 123-129页

作者： wu gang{2. of System ecology, {4. Center for eco Environmental sciences, chinese academy of sciences, beijing 100085, china

The cycling characteristics of nitrogen(N), phosphorus(P) and potassium(K) of the Quercus acutissima and Pinus massoniana mixed forest which is the most common forest type in the Three Gorge Reservoir areas in china, were systematically analyzed. The results showed that N, P and K accumulated in the plant pool and in the litter pool, while total N, P, and K were deficient in the soil pool and in the forest systems. Contents of N in the soil of depth 2.—4. cm were the key factor limiting growth of trees. The biological outside cycling coefficients were 878, 72.5 and 117 times of inside cycling coefficients of N, P and K, respectively. 3392. 102. and 1588 kg of N, P and K return to the litter pool from branches, leaves and throughfall per year, but, 14.31, 132.and 104. kg of N, P and K return to the soil from litter pool per year respectively. It is clear that 58% of N, 87% of P, and 34. of K are lost by surface runoff per year. 54.%, 130%, and 834. of N, P and K withdraw from leaves to branches, 4.99%, 199% and 730% of N, P and K withdraw from branches to trunks per year, respectively.

关键词： nutrient cycling Q. acutissima and P. massoniana mixed forest Three Gorge Reservoir.

Growth pattern of reed in Caogang Lake,Huanghuaihai Plain,china

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Journal of Environmental sciences 1999年第1期11卷 104-109页

作者： Cai Qing hua Institute of Hydrobiology, chinese academy of sciences, wuhan 4.0072.{2. {4., research Center for eco Environmental sciences, chinese academy of sciences, beijing 100085,{2.

The researches about reed growth were mainly concentrated on seasonal dynamics, investigation of reed resource, and comparison of different ecotypes of reed. By means of fractal geometric theory of non linear science, the fractal character of growth pattern of reed, for the purpose of quantitatively exploring the mechanism of reed growth was studied. The way to calculate fractal dimension of reed growth is box dimension (BD) and information dimension (ID). The results showed that the difference between two samplings in May and those among three samplings in June and later were not remarkable for both BD or ID. It was noted that the difference between samplings in and after May is significant. It was demonstrated that the fractal dimension of size distribution of reed ranged from 0 62.5 to 0 8761 The distribution pattern could be statistically divided as two significant periods: the size of reed is quite well distributed at the beginning of reed growth (fractal dimension>0 8), but is irregular in the middle and later growth season (fractal dimensionecosystem.

关键词： fractal pattern growth reed wetland ecosystem.

Impacts of Comorbidity and Mental Shock on Organic Micropollutants in Surface Water During and After the First Wave of COVID-19 Pandemic in wuhan (2.19–2.2.),{4.

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Engineering 2024年第6期37卷 40-48页

作者： Jian Zhao Jin Kang Xiaofeng Cao Rui Bian gang Liu Shengchao Hu Xinghua wu Chong Li Dianchang Wang Weixiao Qi Cunrui Huang Huijuan Liu Jiuhui Qu Center for Water and ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China Hubei Provincial research Institute of Environmental Science Wuhan 430072China Key Laboratory of Drinking Water Science and Technology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Sanitary Engineering Department of Water ManagementFaculty of Civil Engineering and GeosciencesDelft University of TechnologyDelft 2600 GAThe Netherlands china Three Gorges Corporation Wuhan 430010China Vanke School of Public Health Tsinghua UniversityBeijing 100084China

The first pandemic wave of coronavirus disease 2.19(COVID-19)induced a considerable increase in several antivirals and antibiotics in surface *** common symptoms of COVID-19 are viral and bacterial infections,while comorbidities(e.g.,hypertension and diabetes)and mental shock(e.g.,insomnia and anxiety)are ***,little is known about the long-term impacts of comorbidities and mental shock on organic micropollutants(OMPs)in surface ***,we monitored 114.OMPs in surface water and wastewater treatment plants(WWTPs)in wuhan,china,between 2.19 and *** pandemic-induced OMP pollution in surface water was confirmed by significant increases in 2. OMP *** increases in four antihypertensives and one diabetic drug suggest that the treatment of comorbidities may induce OMP ***,cotinine(a metabolite of nicotine)increased 155 times to 187 ngL1,which might be associated with increased ***,the increases in zolpidem and sulpiride might be the result of worsened insomnia and ***,it is reasonable to note that mental-health protecting drugs/behavior also contributed to OMP *** the observed OMPs,telmisartan,lopinavir,and ritonavir were associated with significantly higher {2.logical risks because of their limited WWTP-removal rate and high *** study provides new insights into the effects of comorbidities and mental shock on OMPs in surface water during a pandemic and highlights the need to monitor the fate of related pharmaceuticals in the aquatic environment and to improve their removal efficiencies in WWTPs。

关键词： Coronavirus disease 2.19 Comorbidities Mental shock Micropollutant Surface water

NeurDB: an AI-powered autonomous data system

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Science china(Information sciences) 2024年第10期67卷 129-150页

作者： Beng Chin OOI Shaofeng CAI gang CHEN Yanyan SHEN Kian-Lee TAN Yuncheng wu Xiaokui XIAO Naili XING Cong YUE Lingze ZENG Meihui ZHANG Zhanhao ZHAO School of Computing National University of Singapore College of Computer Science and Technology Zhejiang University department of Computer Science and Engineering Shanghai Jiao Tong University School of Information Renmin University of China School of Computer Science and Technology Beijing Institute of Technology

In the wake of rapid advancements in artificial intelligence(AI), we stand on the brink of a transformative leap in data systems. The imminent fusion of AI and DB(AI×DB) promises a new generation of data systems, which will relieve the burden on end-users across all industry sectors by featuring AI-enhanced functionalities, such as personalized and automated in-database AI-powered analytics, and selfdriving capabilities for improved system performance. In this paper, we explore the evolution of data systems with a focus on deepening the fusion of AI and DB. We present NeurDB, an AI-powered autonomous data system designed to fully embrace AI design in each major system component and provide in-database AI-powered analytics. We outline the conceptual and architectural overview of NeurDB, discuss its design choices and key components, and report its current development and future plan.

关键词： AI$\times$DB in-database AI intelligent data system

New sustainable polymers with on-demand depolymerization property

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Science china Chemistry 2024年第9期67卷 2803-2841页

作者： Yangyang Sun Zesheng An Yanshan Gao Rongrong Hu Ye Liu Hua Lu Xiao-Bing Lu Xuan Pang Anjun Qin Yong Shen Youhua Tao Yu-Zhong Wang Junpeng Wang gang wu Guang-Peng wu Tie-Qi Xu Xing-Hong Zhang Yuetao Zhang Zhenbiao Zhang Jian-Bo Zhu Miao Hong Zhibo Li State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China State Key Laboratory Base of eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSouth China University of TechnologyGuangzhou 510640China State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China beijing National Laboratory for Molecular sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Key Laboratory of Polymer ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The Collaborative Innovation Center for eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)College of ChemistryState Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610064China School of Polymer Science and Polymer Engineering the University of AkronAkronOH 44325USA MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

To combat the crisis of today's synthetic polymers arising from unsustainable production and disposal,it is essential for the synthetic polymer community to reshape the current polymer industry with sustainable *** an emerging class of sustainable polymers,the development of chemically depolymerizable polymers(CDPs),which can undergo closed-loop depolymerization/repolymerization cycles to reproduce virgin polymers without the loss of properties from recovered monomers,offers an ideal solution to preserve finite natural resources,provides a feasible solution to the end-of-life issue of polymer waste,and thereby establishes a circular materials ***,two grand key challenges have been encountered in the establishment of practically useful CDPs:how to balance polymerization and depolymerization ability and how to unify conflicted depolymerizability and physical ***,this critical review article presents our vision for summarizing feasible strategies to overcome the above two significant challenges and the design principles for constructing an ideal CDP by highlighting selected major progress made in this rapidly expanding field.

关键词： chemically depolymerizable polymers sustainable polymers depolymerization monomer recovery degradation plastics