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Precision Fire Hazard Divisions for Collective forest in Southern China

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Chinese forestry Science and Technology 2012年第3期11卷 55-56页

作者： Xu Aijun Huang Xiaoyin Jiang Guangyu Shao Jianlong School of Information Engineering Zhejiang A & F University School of Environmental and Resource Sciences Zhejiang A & F University forest enterprise of longquan city

This paper focuses on how to build the model of precision fire hazard divisions in the level of forest resources *** on 3D GIS technology and characteristics of forest fires in collective forest of southern China,this study utilized Lin’an city,Zhejiang Province as the experimental *** fire factors were divided into 11 indexes from the three categories(social and economic factors,forestry characteristics,and meteorological characteristics) and weighted for ***,three eigenvectors(one for each category) were created to build a nonlinear mathematical model called precision fire hazard divisions for ***,the model was used to optimize and test forest fire hazard divisions with the least *** showed that experimental and theoretical values of error were less than 0.1. Thus,in the experimental area this model and the fire occurrence history matched.

关键词： forest protection forest fire fire hazard division precision classification model least square geographic information system

Disease Law and Forecasting of the Needle Blight ofPinus sylvestris var. mongolica

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Journal of forestry Research 1997年第2期8卷 104-107页

作者：李鹏飞葛玉祥张希明王道君王君吴长友 Animal and Plant Quarantine Bureau of Manzhouli Manzhouli Inner Mongolia The forest enterprise of Honghuarji Inner Mongolia Honghuarji forest enterprise Inner Mongolia

Fixed quadrates were established in different stands. In continued six years, the occurring period, occurring amounts and the relation between epidemic disease and environmental factors were investigated according to spraying lawsof spores and accounting measures of disease ranking. The occuring peak period of the disease was from the last ten days ofMay to the second ten days of June. The epidemic period was from the last ten days of June to the second ten days of Julyand the initial decease period was from the last ten days of July to the beginning of September. The change of the diseasedepended on air temperature, relative humidity and precipitation. A multiple linear regression model was established usingcomputer, which can predict the disease index(Y) of 10 days later, with more than 95% reliability

关键词： Pinus sylvestris var mongolica Disease Needle blight Septoria pini-putnilae Sawada Dothistroma pini Hulbary Forecast technique Pathogen

Biology and damage traits of emerald ash borer planipennis Fairmaire）in China

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Insect Science 2007年第5期14卷 367-373页

作者： XIA WEI YUN WU RICHARD REARDON TIE-HUAN SUN MIN LU JIANG-HUA SUN forest Protection Institute of Heilongjiang Province Harbin China USDA forest Service Forest Health Technology Enterprise Team Morgantown West Virginia USA forest Pest Prevention and Quarantine Station of Tianjin Tianjin China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Beijing China

Emerald ash borer （Agrilus planipennis Fairmaire）（Coleoptera： Buprestidae） is a major stem borer of ash （Fraxinus spp.）. It is univoltine in Tianjin, while it is semivoltine in Heilongjiang Province, and both univoltine and semivoltine in Changchun, Jilin Province, where the majority is univoltine. The longevity of emerald ash borer adults is 17.2 ± 4.6 days （n = 45）, eggs 9.0 5：1.1 days （n = 103）, univoltine larvae 308 days, semivoltine larvae 673 days, and pupae 61.2 ± 1.6 days （n = 45）. It takes about 100 days from the time larvae bore into the phloem to when they complete the pupal cell. In a 10-year-old velvet ash （Fraxinus velutina Tort.） plantation in Tianjin, emerald ash borer preferred to oviposit on the regions of boles from 50-150 cm above ground, accounting for 76.7% of the total girdling. Girdling on the south side of the tree boles accounted for 43.40% of the total girdling. The emerald ash borer population density is higher at the edge of the plantation compared with the center.

关键词： biology damage traits emerald ash borer life history

Non-native plant species richness and influence of greenhouses and human populations in the conterminous United States

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Ecological Processes 2023年第1期12卷 388-401页

作者： Brice B.Hanberry USDA forest Service Rocky Mountain Research StationRapid CitySD 57702USA

Background One issue in invasive plant ecology is identification of the factors related to the invasion process that increase number of non-native *** invasion by non-native species increases,so does the probability that some non-native species will become harmful,or classified as invasive species,which disrupt natural ecosystems with attendant economic and social costs.I quantified patterns of how non-native species richness varied with vegetation types and human *** evaluate the relative importance of different predictor variables for invasion pathways in the conterminous United States,I modeled non-native plant species richness by county compared to current and historical human populations;greenhouses and nurseries;railroads,pipelines,transmission lines,and oil and gas wells;and land covers of impervious surface,development intensity categories,agriculture,and vegetation types.I also modeled these variables within vegetation types,excluding vegetation *** To summarize patterns,non-native plant species richness increased from 72 to 200 with increasing human population density *** and forest land use mosaics had the greatest mean number of non-native plant species,ranging from 121 to 166,whereas grasslands and grassland mosaics had the least number of non-native plant species,about *** modeling variable importance,all combined variables had R^(2)values of 56%(random forests regressor)and 54%(cubist regressor)for predictions of withheld observations of non-native plant species rich-ness,with greenhouse density and percent forestlands as most influential *** variables of greenhouses(R^(2)=29%),historical and current human populations(R^(2)=27%and 23%),impervious surface(25%),and medium intensity development(23%)were most associated with non-native plant species *** vegetation types,greenhouse and historical human population densities were influential variables particularly in forestlands,shrubland

关键词： Agriculture Energy forest Grassland Invasive Propagule Rural Transport Urban

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Trajectory from beech and oak forests to eastern broadleaf forests in Indiana, USA

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Ecological Processes 2019年第1期8卷 21-28页

作者： Brice B.Hanberry USDA forest Service Rocky Mountain Research StationRapid CitySD 57702USA

Background:Historical forests(circa 1799 to 1846)of Indiana were predominantly composed of American beech(25%of all trees)and upland oaks(27%of all trees).I compared historical forest composition,using studies of smaller areas to approximate composition for uncommon species or genera(forest types,to current forest composition and forest types in Indiana.I also compiled published historical density estimates from small studies and estimated current density for the ***:Current forests are diverse with an even composition of many eastern broadleaf *** addition to upland oaks,which decreased to 13%of all trees,only sugar maple currently comprises greater than 10%of all *** increasing species were yellow-poplar,red maple,black cherry,and eastern *** redcedar increased from no presence to one of the most abundant ten species(≥3.5%of composition),similarly to the pine genus,becoming more common currently than American *** or oak or beech-oak forest types(≥24%of all trees)became eastern broadleaf forests,with no dominant species,and black cherry,red maple,and eastern redcedar forest types now *** of historical oak or beech forests ranged from 28 trees per hectare to 175 trees per hectare,which probably represent savannas and *** mean density of Indiana forests is 385 trees per hectare,ranging from 180 trees per hectare to 450 trees per *** forests likely contain dense layers of woody vegetation,filling the midstory and replacing herbaceous vegetation in the ground ***:Historically dominant beech and oak forests in the eastern United States have transitioned to an alternative state of closed eastern broadleaf forests due to uncontrolled establishment of many tree species.

关键词： Fire Historical Range of variability Transition

Recent shifts in shade tolerance and disturbance traits in forests of the eastern United States

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Ecological Processes 2019年第1期8卷 391-401页

作者： Brice B.Hanberry Rocky Mountain Research Station USDA Forest ServiceRapid CitySD 57702USA

Background:Current forests of the eastern USA have the potential to succeed in composition to more shade-tolerant ***,long-term processes of transition from fire-tolerant tree species to fire-sensitive species and effects of current land use on forests may interfere with successional ***:I examined if forests in three regions have increased in shade tolerance and if life history strategy groups that represent response to disturbance(i.e.,fire-tolerance,early-successional species based on low shade tolerance,mid-successional species,late-successional species,and trees valued for traits related to short harvest rotations)have changed,using forest Inventory and Analysis surveys,adjusted for comparison,and generalized linear mixed models to assess approximately 30 year trends,with adjustments to equalize different survey ***:Although statistically significant,a slight increase of 2 to 4%in regional mean shade tolerance may not be ecologically *** the central East,mid-successional species replaced early-successional species and early-successional species replaced fire-tolerant oaks,resulting in an overall shift from fire-tolerant oaks to mid-successional *** fire-tolerant pine species and increased planted pine species were the major changes in the northern Southeast and Coastal ***:The successional process of increased composition by shade-tolerant species over time was overshadowed by land use changes that resulted in decreased fire-tolerant species and increased planted ***,frequent land use disturbance may continue to prevent the slow progress of compositional succession to very shade-tolerant species.

关键词： Disturbance Eastern United States Fire Land use Mesophication Oak Pine Succession Traits

Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls

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Nano-Micro Letters 2025年第1期17卷 98-134页

作者： Yang Shi Mingjun Wu Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen Co‑Innovation Center of Efficient Processing and Utilization of forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037People’s Republic of China State Key Laboratory of Efficient Production of forest Resourced Beijing Forestry UniversityQinghua East Road 35Haidian DistrictBeijing 100083People’s Republic of China Department of Physics Faculty of Sciences‑ArarNorthern Border UniversityArar 91431Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 1109921944 TaifSaudi Arabia Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Integrated Composites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024People’s Republic of China Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products International Joint Research Center for Biomass MaterialsSouthwest Forestry UniversityKunming 650224People’s Republic of China School of Science Henan Agricultural UniversityZhengzhou 450002People’s Republic of China

Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass *** materials offer numerous advantages such as being lightweight,porous,and *** to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding *** concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding *** particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be *** preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and *** composite methods and fillers of various biomass materials were *** paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.

关键词： Biomass materials Electromagnetic interference shielding Micro-nano structure interface control Conductivity

IMPEDIMENTS AND SOLUTIONS TO NATURAL RESOURCES FOR SUSTAINABLE DEVELOPMENT IN CHINA

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Journal of Northeast forestry University 1995年第2期6卷 77-80页

作者：刘艳红孙玉军李艳明 Northeast forestry University Harbin China Mudanjiang city forest Bureau Mudanjiang City Heilongjiang Province

The paper introduces the situation of studies on sustainable development in the world and China’s response to the topic. The impediments of natural resources to realize sustainable development in China are analyzed. ... 详细信息

关键词： Sustainable development Natural resources China

Inventory of aspen trees in spruce dominated stands in conserva-tion area

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forest Ecosystems 2015年第2期2卷 143-154页

作者： Matti Maltamo Annukka Pesonen Lauri Korhonen Jari Kouki Mikko Vehmas Kalle Eerik?inen University of Eastern Finland School of Forest Science Blom Kartta Oy city of Joensuu Natural Resources Institute Finland Joensuu Unit

Background： The occurrence of aspen trees increases the conservation value of mature conifer dominated forests. Aspens typically occur as scattered individuals among major tree species, and therefore the inventory of aspens is challenging. Methods： We characterized aspen populations in a boreal nature reserve using diameter distribution, spatial pattern, and forest attributes： volume, number of aspens, number of large aspen stems and basal area median diameter. The data were collected from three separate forest stands in Koli National Park, eastern Finland. At each site, we measured breast height diameter and coordinates of each aspen. The comparison of inventory methods of aspens within the three stands was based on simulations with mapped field data. We mimicked stand level inventory by locating varying numbers of fixed area circular plots both systematically and randomly within the stands. Additionally, we also tested if the use of airborne laser scanning （ALS） data as auxiliary information would improve the accuracy of the stand level inventory by applying the probability proportional to size sampling to assist the selection of field plot locations. Results： The results showed that aspens were always clustered, and the diameter distributions indicated different stand structures in the three investigated forest stands. The reliability of the volume and number of large aspen trees varied from relative root mean square error figures above 50% with fewer sample plots （5-10） to values of 25%-50% with ]0 or more sample plots. Stand level inventory estimates were also able to detect spatial pattern and the shape of the diameter distribution. In addition, ALS-based auxiliary information could be useful in guiding the inventories, but caution should be used when applying the ALS-supported inventory technique. Conclusions： This study characterized European aspen populations for the purposes of monitoring and management of boreal conservation areas. Our results suggest tha

关键词： Diameter distribution Historical continuity Inventory LiDAR Populus tremula L Simulation Spatial arrangement Stand characteristics