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Journal of forestry Research 2013年第3期24卷 547-552页

作者： LI Ling SUN Fan HU Ji-hua YIN Yanbao CHI De-fu school of forestry Northeast Forestry University

We used scanning electron microscope （SEM） to observe the ultrastructure of stridulating organs in Xylotrechus rusticus L. We com- pared the morphological structure and size of stridulating organs, the numbers of a tooth-like part used in stridulation and its presence in fe- males and males of this beetle. The alarm sound of X.. rusticus was re- corded first when it was stimulated, then we tested behavioral responses to this alarm sound. The alarm sound ofX. rusticus has a warning effect on conspecifics.

关键词： Xylotrechus rusticus L. stridulating organ behavioral re-sponse to sound

Forest type identification by random forest classification combined with SPOT and multitemporal SAR data

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Journal of forestry Research 2018年第5期29卷 1407-1414页

作者： Ying Yu Mingze Li Yu Fu school of forestry Northeast Forestry University

We developed a forest type classification technology for the Daxing＇an Mountains of northeast China using multisource remote sensing data.A SPOT-5 image and two temporal images of RADARSAT-2 full-polarization SAR were used to identify forest types in the Pangu Forest Farm of the Daxing＇an *** types were identified using random forest（RF） classification with the following data combination types： SPOT-5 alone,SPOT-5 and SAR images in August or November,and SPOT-5 and two temporal SAR *** identified many forest types using a combination of multitemporal SAR and SPOT-5 images,including Betula platyphylla,Larix gmelinii,Pinus sylvestris and Picea koraiensis *** accuracy of classification exceeded 88% and improved by 12% when compared to the classification results obtained using SPOT data *** classification using a combination of multisource remote sensing data improved classification accuracy compared to that achieved using single-source remote sensing data.

关键词： Random forest classification Multitemporal Multisource remote sensing data Polarization decomposition

A new species, first report of a male and new distributional records for five species of Oligosita Walker(Hymenoptera:Trichogrammatidae) from China

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Journal of forestry Research 2019年第3期30卷 1123-1130页

作者： Sizhu Liu Chengde Li school of forestry Northeast Forestry University

Seven species of the genus Oligosita, a wellknown cosmopolitan genus of the family Trichogrammatidae that comprise egg parasitoids of coleopteran, hemipteran, lepidopteran and thysanopteran insects, are reviewed. Oligosita xinyangensis sp. nov.(Hymenoptera, Trichogrammatidae) is described in detail and illustrated;the male of O. nigroflagellaris Lin is reported for the first time. New distributional data are provided for O. japonica Yashiro, O. mediterranea Nowicki, O. pallida Kryger, O. polioptera Lin and O. shibuyae Ishii from China, and a key to all the Chinese species of the genus is given.

关键词： Chalcidoidea Oligositinae Oligositini Parasitoid Taxonomy

First report of Platystethynium with description of a new species and two other new records from China (Hymenoptera:Mymaridae)

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Journal of forestry Research 2016年第1期27卷 203-207页

作者： Xiangxiang Jin Chengde Li school of forestry Northeast Forestry University

Platystethynium glabrum Jin et Li sp. nov. is described from China, and the genus is new to Chinese insect fauna. Diagnostic characters for the new species are given in comparison with the apparently closely related P. onomarchicidum. Two other mymarid species are also newly recognized from China： Mymar africanum Annecke and Anagroidea marina Triapitsyn et Berezovskiy.

关键词： Mymaridae Platystethynium Mymar.Anagroidea Taxonomy China

Analysis of PM2.5 concentrations in Heilongjiang Province associated with forest cover and other factors

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Journal of forestry Research 2019年第1期30卷 269-276页

作者： Yu Zheng San Li Chuanshan Zou Xiaojian Ma Guocai Zhang College of Science Northeast Forestry University school of forestry Northeast Forestry University

Atmospheric particulate matter(PM2.5) seriously influences air quality. It is considered one of the main environmental triggers for lung and heart diseases. Air pollutants can be adsorbed by forest. In this study we investigated the effect of forest cover on urban PM2.5 concentrations in 12 cities in Heilongjiang Province,China. The forest cover in each city was constant throughout the study period. The average daily concentration of PM2.5 in 12 cities was below 75 lg/m^3 during the non-heating period but exceeded this level during heating period. Furthermore, there were more moderate pollution days in six cities. This indicated that forests had the ability to reduce the concentration of PM2.5 but the main cause of air pollution was excessive human interference and artificial heating in winter. We classified the 12 cities according to the average PM2.5 concentrations. The relationship between PM2.5 concentrations and forest cover was obtained by integrating forest cover, land area,heated areas and number of vehicles in cities. Finally,considering the complexity of PM2.5 formation and based on the theory of random forestry, we selected six cities and analyzed their meteorological and air pollutant data. The main factors affecting PM2.5 concentrations were PM10,NO_2, CO and SO_2 in air pollutants while meteorological factors were secondary.

关键词： Forest cover Heilongjiang Province Influencing factor PM2.5 concentrations Random forest

Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia

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Atmospheric and Oceanic Science Letters 2025年第01期 48-53页

作者： Yiying Zhu Hesong Wang Anzhi Zhang school of Ecology and Nature Conservation Beijing Forestry University Key Laboratory of Regional Climate and Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences College of forestry and Landscape Architecture Xinjiang Agricultural University

目前对于亚洲森林在应对气候变化和人类活动干扰方面的研究相对较少.本研究利用BFAST突变检测方法,分析了东亚,南亚和东南亚的增强植被指数(EVI)长时间序列中检测到的森林扰动和恢复情况.结果显示, 2000年至2022年期间,约20%的森林经历... 详细信息

目前对于亚洲森林在应对气候变化和人类活动干扰方面的研究相对较少.本研究利用BFAST突变检测方法,分析了东亚,南亚和东南亚的增强植被指数(EVI)长时间序列中检测到的森林扰动和恢复情况.结果显示, 2000年至2022年期间,约20%的森林经历了扰动,且受到扰动的森林面积呈增加趋势,东南亚国家受扰动的影响更为严重.在扰动事件发生后, 95%的森林具有较好的恢复能力,能够在受到扰动后的一段时间后恢复过来,其中约有三分之二的森林在2022年时已经恢复到了较扰动前更好的状态.

关键词：森林生态系统增强型植被指数突变检测方法扰动恢复力

Clonal variations in nutritional components of Pinus koreansis seeds collected from seed orchards in Northeastern China

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Journal of forestry Research 2016年第2期27卷 295-311页

作者： Zhen Zhang Hanguo Zhang Chuanping Yang Lei Zhang Jia Du Ying Jiang Research Institute of Subtropical forestry Chinese Academy of Forestry school of forestry Northeast Forestry University school of Municipal and Environmental Engineering Harbin Institute of Technology

From four Korean pine （Pinus koraiensis） orchards, 60 clones were selected and analyzed for the fatty acid and amino acid components of the seeds to reveal the variations and correlations of the seed characteristics among the clonal source orchards and clones. The nutri- tional components of the seeds of the P. koraiensis trees exhibited rich genetic variation; the variation coefficient of the fatty acids was 2.24-66.83 %, while the variation coefficient of the amino acids was 14.70-38.88 %. Rela- tively high genetic-improvement potential exists for the nutritional components of the seeds. The phenotypic dif- ferentiation of the fatty acid and amino acid components reveals that variation within the population （85.18 %） was the primary source for the variation of the fatty acid components; variation among the orchards （63.08 %） was the primary source of the variation of the amino acid components. Data drawn from various clonal source orchards all showed that the seed characteristics were highly controlled by heritability （h2 〉 80 %）, and the seed characteristics of the P. koraiensis trees exhibited a similar genetic gain trend. The principal components were ana- lyzed to obtain the comprehensive principal component value for each clonal seed orchard. Twelve clones were selected based on a clonal selection rate of 20 %. Corre- lation and multiple stepwise-regression analyses were conducted, considering different location conditions, to reveal the stable correlations between the seed character- istics to facilitate improvements of the seed yield of P. koraiensis trees and the clonal selection. Species of real characteristics in P. koraiensis were controlled by higher heritability. Genetic gain was obtained by selecting of superior clones.

关键词： Fatty acid Amino acid Clone Multi-characteristic selection

Object-based forest gaps classification using airborne LiDAR data

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Journal of forestry Research 2019年第2期30卷 617-627页

作者： Xuegang Mao Jiyu Hou school of forestry Northeast Forestry University school of Geographic and Oceanographic Sciences Nanjing University

Object-based classification differentiates forest gaps from canopies at large regional scale by using remote sensing data. To study the segmentation and classification processes of object-based forest gaps classification at a regional scale, we sampled a natural secondary forest in northeast China at Maoershan Experimental Forest *** light detection and ranging(LiDAR; 3.7 points/m2) data were collected as the original data source and the canopy height model(CHM) and topographic dataset were extracted from the LiDAR data. The accuracy of objectbased forest gaps classification depends on previous segmentation. Thus our first step was to define 10 different scale parameters in CHM image segmentation. After image segmentation, the machine learning classification method was used to classify three kinds of object classes, namely,forest gaps, tree canopies, and others. The common support vector machine(SVM) classifier with the radial basis function kernel(RBF) was first adopted to test the effect of classification features(vegetation height features and some typical topographic features) on forest gap *** the different classifiers(KNN, Bayes, decision tree,and SVM with linear kernel) were further adopted to compare the effect of classifiers on machine learning forest gaps classification. Segmentation accuracy and classification accuracy were evaluated by using Mo¨ller's method and confusion metrics, respectively. The scale parameter had a significant effect on object-based forest gap segmentation and classification. Classification accuracies at different scales revealed that there were two optimal scales(10 and 20) that provided similar accuracy, with the scale of 10 yielding slightly greater accuracy than 20. The accuracy of the classification by using combination of height features and SVM classifier with linear kernel was91% at the optimal scale parameter of 10, and it was highest comparing with other classification classifiers, such as SVM RBF

关键词： Forest gap Scale segmentation Classification feature LiDAR CHM Object based Machine learning

Fractional Fourier transform of Lorentz beams

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Chinese Physics B 2009年第7期18卷 2779-2784页

作者：周国泉 school of Sciences Zhejiang Forestry University

This paper introduces Lorentz beams to describe certain laser sources that produce highly divergent *** fractional Fourier transform （FRFT） is applied to treat the propagation of Lorentz *** on the definition of convolution and the convolution theorem of the Fourier transform,an analytical expression for a Lorentz beam passing through a FRFT system has been *** using the derived formula,the properties of a Lorentz beam in the FRFT plane are illustrated numerically.

关键词： Lorentz beam fractional Fourier transform propagation properties

Nonparaxial propagation of a vectorial apertured off-axis Lorentz beam

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Chinese Physics B 2009年第5期18卷 1853-1860页

作者：周国泉 school of Sciences Zhejiang Forestry University

Based on the vectorial Ftayleigh-Sommerfeld integral formula and the complex Gaussian expansion of the hardedge aperture function, an analytical propagation expression for a nonparaxial vectorial off-axis Lorentz beam passing through a rectangular aperture is derived. The unapertured case, the far field expression and the scalar paraxial result are also presented as special cases of the general formulae, respectively. Some numerical examples are also given to show the propagation characteristics of a nonparaxial vectorial off-axis Lorentz beam through a rectangular aperture. It is indicated that the f parameter, the off-axis displacement and the truncation parameter all play an important role in determining nonparaxial propagation behaviour.

关键词： vectorial Rayleigh-Sommerfeld integral nonparaxial vectorial off-axis Lorentz beam,rectangular aperture