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Ground peak identification in dense shrub areas using large footprint waveform LiDAR and Landsat images

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International Journal of Digital Earth 2015年第10期8卷 805-824页

作者： Wei Zhuang Giorgos Mountrakis Department of environmental Resources Engineering State University of New York College of Environmental Science and ForestrySyracuseNYUSA

Large footprint waveform LiDAR data have been widely used to extract tree *** heights are typically estimated by subtracting the top height from the *** to the top height detection,the identification of the ground peak in awaveform is more *** is particularly evident in ground detection in shrubareas,where the reflection of the shrub canopy may significantly overlap with theground *** tackle this problem,a novel method based on Partial Curve-Fitting(PCF)of the shrub peak was developed to detect the ground *** that the PCF method improves ground identification by 32-42%,comparedto existing *** offer further improvement,a Multi-Algorithm IntegrationClassifier(MAIC)was built to fuse multiple ground peak algorithms and selectivelyapply the best method for each waveform *** PCF ground peak identificationmethod along with the MAIC-based fusion is expected to significantly improve grounddetection and shrub height estimation,thus assisting biodiversity,forest succession,and carbon sequestration studies,while offering an early example of future multiplealgorithm integration.

关键词： ground identification large footprint waveform LiDAR shrub partial fitting algorithmic fusion

Comparative efficacy of gypsy moth(Lepidoptera:Erebidae)entomopathogens on transgenic blight-tolerant and wild-type American,Chinese,and hybrid chestnuts(Fagales:Fagaceae)

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Insect science 2020年第5期27卷 1067-1078页

作者： Aaron J.Brown Andrew E.newhouse William A.Powell Dylan Parry Department of environmental and Forest Biology College of Environmental Science and ForestryState University of New YorkSyracuseNY13210USA

American chestnut(Castanea dentata[Marsh.]Borkh.)was once the dominant hardwood species in Eastern North America before an exotic fungal pathogen,Cryphonec-tria parasitica(Murrill)Barr,functionally eliminated it across its *** promising approach toward restoring American chestnut to natural forests is development of blight-tolerant trees using genetic ***,transformation and related processes can result in unexpected and unintended phenotypic changes,potentially altering ecologi-cal *** assess unintended tritrophic impacts of transgenic American chestnut on plant herbivore interactions,gypsy moth(Lymantria dispar L.)caterpillars were fed leaf disks excised from two transgenic events,Darling 54 and Darling 58,and four control American chestnut *** disks were previously treated with an LDso dose of either the speces-specific Lymantria dispar multiple nucleopolyhedrovirus(LdMNPV)or the generalist pathogen Bacillus thuringiensis ***(Btk).Mortality was quantified and compared to water blank *** genotype had a strong efect on the efficacies of both *** mortality from Btk-treated foliage from only one transgenic event,Darling 54,differed from its isogenic progenitor,Ellis l,but was similar to an unre-lated wild-type American chestnut *** efficacy was unaffected by genetic *** suggest that although genetic modification of trees may affect interactions with other nontarget organisms,this may be due to insertion effects,and varia-tion amnon diMterent genvtypes(wlether uasgeic ul wild-typc)iupaults a giealci change in response than transgene presence.

关键词： Bacillus thuringiensis LdMNPV nontarget restoration tri-trophic unin-tended effects

Speciation, sources, and risk assessment of heavy metals in suburban vegetable garden soil in Xianyang City, Northwest China

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Frontiers of Earth science 2018年第2期12卷 397-407页

作者： Lijun WANG Wendong TAO Richard C. SMARDON Xue XU Xinwei LU Department of environmental science College of Tourism and Environment Shaanxi Normal University Xi'an 710119 China college of environmental science and forestry State University of New York NY 13201 USA

Intensive anthropogenic activities can lead to soil heavy metal contamination resulting in potential risks to the environment and to human health. To reveal the concentrations, speciation, sources, pollution level, and ecological risk of heavy metals in vegetable garden soil, a total of 136 soil samples were collected from three vegetable production fields in the suburbs of Xianyang City, Northwest China. These samples were analyzed by inductively coupled plasma- atomic emission spectrometry and atomic fluorescence spectrometry. The results showed that the mean concentrations of Cd, Co, Cu, Mn, Pb, Zn, and Hg in vegetable garden soil were higher than the corresponding soil element background values of Shaanxi Province. The heavy metals studied in vegetable garden soil were primarily found in the residual fraction, averaging from 31.26% (Pb) to 90.23% (Cr). Considering the non-residual fractions, the mobility or potential risk was in the order of Pb (68.74%)>Co (60.54%)>Mn (59.28%) >Cd (53.54%) ≫Ni (23.36%) >Zn (22.73%)>Cu (14.93%)>V (11.81%)>Cr (9.78%). Cr, Mn, Ni, V, and As in the studied soil were related to soilforming parent materials, while Cu, Hg, Zn, Cd, Co, and Pb were associated with the application of plastic films, fertilizers, and pesticides, as well as traffic emissions and industrial fumes. Cr, Ni, V, and As presented low contamination levels, whereas Co, Cu, Mn, Pb, and Zn levels were moderate, and Cd and Hg were high. Ecological risk was low for Co, Cr, Cu, Mn, Pb, Zn, and As, with high risk observed for Cd and Hg. The overall pollution level and ecological risk of these heavy metals were high.

关键词： heavy metal speciation source pollution level ecological risk vegetable garden soil

FORMATION AND MICROSTRUCTURE OF POLYETHYLENE MICROPOROUS MEMBRANES THROUGH THERMALLY INDUCED PHASE SEPARATION

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Chinese Journal of Polymer science 1995年第1期13卷 7-19页

作者：李文俊袁又欣 CABASSO Israel Department of Macromolecular science Fudan University Shanghai 200433China The Polymer Research Institute State University of New YorkCollege of Environmental Science and Forestry Syracuse New York 13210 U. S. A.

Microporous membranes of low-high density polyethylene and their blends were prepared bythermally-induced phase separation of polymer/long-aliphatic chain alcohol (diluent) *** microstructures of this particular membrane, which depends on the diluent properties,polymer concentration and cooling rate, were observed by scanning electron microscopy.'Beehive-type,'leafy-like, and lacy porous structure morphologies can be formed,depending onthe blend composition and phase separation conditions, which were discussed by the polymer anddiluent crystallization processes.

关键词： Microporous membrane Membrane preparation Membrane structure Phase separation Polyethylene membrane

Estimation of Ecological Water Requirements Based on Habitat Response to Water Level in Huanghe River Delta,China

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Chinese Geographical science 2010年第4期20卷 318-329页

作者： CUI Baoshan HUA Yanyan WANG Chongfang LIAO Xiaolin TAN Xuejie TAO Wendong state Key Joint Laboratory of environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China Department of environmental Resources and Forest Engineering College of Environmental Science and Forestry State University of New York NY 13210 USA

In recent years,wetland ecological water requirements (EWRs) have been estimated by using hydrological and functional approaches,but those approaches have not yet been integrated for a whole *** paper presents a new method for calculating wetland EWRs,which is based on the response of habitats to water level,and determines water level threshold through the functional integrity of *** show that in the Huanghe (Yellow) River Delta water levels between 5.0 m and 5.5 m are required to maintain the functional integrity of the wetland at a value higher than *** of the dominant plants in the delta,Phragmites australis,tolerates water level fluctuation of about ± 0.25 m without the change in wetland functional *** minimum,optimum and maximum EWRs for the Huanghe River Delta are 9.42×106 m3,15.56×106 m3 and 24.12×106 m3 with water levels of 5.0 m,5.2 m and 5.5 m,corresponding to functional integrity indices of 0.70,0.84 and 0.72,respectively.A wetland restoration program has been performed,which aims to meet these EWRs in attempt to recover from losses of up to 98% in the delta's former wetland area.

关键词： water level-habitat response functional integrity ecological water requirements wetland Huanghe River Delta

A Review of Hydrophobic Nanocellulose and Its Applications

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Paper And Biomaterials 2021年第2期6卷 35-42页

作者： Jinglei Xie Shijie Liu Department of Chemical Engineering State University of New York—College of Environmental Science and ForestrySyracuseNY13210USA

Nanocellulose is of great interest in various areas nowadays as a natural nanostructured ***,in many applications,the high hydrophilicity due to a large number of hydroxyl groups is not *** hydrophobic modification of nanocellulose can thus increase its *** work reviewed recent developments of methods for nanocellulose hydrophobic modification,through physical adsorption and chemical *** applications of hydrophobic nanocellulose were also reviewed.

关键词： nanocellulose hydrophobic modification physical adsorption chemical grafting applications

Geographic variation in larval cold tolerance and exposure across the invasion front of a widely established forest insect

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Insect science 2024年第6期31卷 1930-1942页

作者： Petra Hafker Lily M.Thompson Jonathan A.Walter Dylan Parry Kristine L.Grayson Department of Biology University of RichmondRichmondVAUSA Department of Entomology Cornell UniversityIthacaNYUSA Department of forestry and environmental Conservation Clemson UniversityClemsonSCUSA Department of environmental sciences University of VirginiaCharlottesvilleVAUSA Department of environmental Biology State University of New YorkCollege of Environmental Science and ForestrySyracuseNYUSA

Under global climate change,high and low temperature extremes can drive shifts in species *** the range of a species,thermal tolerance is based on acclimatization,plasticity,and may undergo selection,shaping resilience to temperature *** this study,we measured variation in cold temperature tolerance of early instar larvae of an invasive forest insect,Lymantria dispar dispar L.(Lepidoptera:Erebidae),using populations sourced from a range of climates within the current introduced range in the Eastern United *** tested for population differences in chill coma recovery(CCR)by measuring recovery time following a period of exposure to a nonlethal cold temperature in 2 cold exposure experiments.A 3rd experiment quantified growth responses after CCR to evaluate sublethal *** results indicate that cold tolerance is linked to regional climate,with individuals from populations sourced from colder climates recovering faster from chill *** this geographic gradient is seen in many species,detecting this pattern is notable for an introduced species founded from a single point-source *** demonstrate that the cold temperatures used in our experiments occur in nature during cold spells after spring egg hatch,but impacts to growth and survival appear *** expect that population differences in cold temperature performance manifest more from differences in temperature-dependent growth than acute *** intraspecific variation in cold tolerance increases our understanding of the role of climatic gradients on the physiology of an invasive species,and contributes to tools for predicting further expansion.

关键词： chill coma recovery forest insect geographic gradient Lymantria dispar spring cold spell thermal performance

Deposition of water-soluble inorganic ions in PM_(2.5) in a typical forestry system in Beijing,China

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Forest Ecosystems 2018年第4期5卷 486-497页

作者： Junqi Ding Xiaoxiu Lun Weifang Ma Lu Zhao Yingying Cao Fengbin Sun Renna Li college of environmental science and Engineering Beijing Forestry University state Key Laboratory of environmental Criteria and Risk Assessment Chinese Academy of Environmental Sciences School of Soil and Water Conservation Beijing Forestry University

Background: Rapid economic development in China has resulted in an increase in severe air pollution in city groups such as the Beijing-Tianjin-Hebei Metropolitan Region. PM2.5(fine particles with an aerodynamic equivalent diameter of 2.5 μm or less) is one of the most important pollutants. The deposition process is an important way of removing particles from the air. To evaluate the effect of an urban forest on atmospheric particle removal, a concentration gradient method was used to measure the deposition velocities of water-soluble inorganics in PM2.5 in two national forest parks in Beijing, China. The following eight water-soluble inorganic ions in PM2.5 were investigated: sodium, ammonium, potassium, magnesium, calcium, chloride, nitrate, and ***: Samples were taken from two sites in Beijing from the 7 th to the 15 th May, 2013. The concentrations of water-soluble inorganic ions were analyzed with ion chromatography. We used the concentration gradient technique to estimate the deposition flux and velocity. To determine the relationships between leaf traits and particle accumulation, typical leaf samples from each selected species were studied using scanning electron ***: The total deposition flux and total deposition velocity during the daytime were higher than those at *** showed the biggest deposition flux and velocity at both study sites, whereas the other ions showed different trends at each site. Result from higher proportion of coniferous to broadleaved trees, the total deposition flux of the eight ions measured in Jiufeng National Forest Park was greater than that in Olympic Forest ***: The deposition velocity was affected by meteorological conditions such as wind speed, temperature,and humidity. The deposition velocity was also influenced by tree species. The surface of plants is an important factor influencing particle deposition. The results of this study may help in assessing the effects of forestry sy

关键词： Fine particle Water-soluble inorganics Forest Dry deposition Deposition velocity

Enhanced singlet oxygen generation by hybrid Mn-doped nanocomposites for selective photo-oxidation of benzylic alcohols

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Nano Research 2020年第6期13卷 1668-1676页

作者： Zhi-Jun Li Shuya Li Andrew Hunter Davis Elan Hofman Gyu Leem Weiwei Zheng Department of Chemistry Syracuse UniversitySyracuseNY13244USA Department of Chemistry State University of New York College of Environmental Science and ForestrySyracuseNY13210USA The Michael M.Szwarc Polymer Research Institute SyracuseNY13210USA

Transition-metal ions doped nanocrystals(NCs),specifically Mn-doped NCs,hold great potential in the field of photocatalysis,especially,to improve photocatalytic performance for singlet oxygen(1O2)***,we report the design of a novel Mn-doped NC-based nanocomposites,specifically,silica-coated Mn-doped CdS/ZnS NCs decorated with Pt NCs(denoted as Mn-NCs@SiO2-Pt),which enhance photocatalytic 1O2 *** to the long-lived Mn excited state(on the order of ms),the energy-transfer between Mn-NCs and molecular oxygen is facilitated with the assistance of the Pt NCs adhered to the Mn-NC@SiO2 ***,the Mn-NCs@SiO2-Pt composites,integrate the advantages of Mn-doped NCs,a protective silica layer,and Pt NCs to exhibit excellent catalytic activity and selectivity for the selective oxidation of primary benzylic alcohols to aldehydes through an 1O2 engaged oxidation process under visible-light *** work paves the way for enhancing catalytic performance via facilitated energy transfer relaxation by utilizing the long-lived excited-state of Mn2+dopant ions in nanocomposites.

关键词： doped nanocrystals energy transfer photocatalysis singlet oxygen selective oxidation