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Coexistence of two sympatric and morphologically similar bat species Rhinolophus a nis and Rhinolophus pearsoni

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Progress in Natural Science:Materials International 2008年第5期18卷 523-532页

作者： Tinglei Jiang, Jiang Feng , Keping Sun, Jing Wang college of urban and environmental sciences, northeast normal university, Changchun 130024, China college of urban and environmental sciences Northeast Normal University Changchun 130024 China

Ecologists have long focused on the coexistence of sympatric species. Here, we investigated two horseshoe bat species, Rhinolophus a nis and Rhinolophus pearsoni inhabited in the same cave, for their foraging strategies, niche di erentiation, prey selection, and their coexistence status. These two species of horseshoe bats were di erent in the dominant frequency of their echolocation calls, but similar in their morphology. We found evidence for prey selectivity although there was a high degree of overlap in prey categories and sizes. R. a nis and R. pearsoni foraged on 16 and 7 categories insects, respectively, with Pyralidae, Geometridae, Melolonthidae dominating their diets. The degree of trophic niche overlap was 0.69. Pairwise comparisons suggested that there was no obvious di erentiation in prey categories and size. However, high prey availability in the environment (Simpson diversity index = 0.79 and Margalef richness index = 4.12) contributed to their coexistence by dampening the interspeci c competition. Since there are one or more mechanisms facil- itating species coexistence in a community, our results suggest that the spatial niche di erentiation in foraging microhabitats and in for- aging habitats at landscape scale may promote the coexistence of the two bat species. However, additional eld data are needed to con rm this speculation.

关键词： Bats Species coexistence Foraging strategies Niche di erentiation Prey richness

Regional Evolution Features and Coordinated Development Strategies for northeast China

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Chinese Geographical Science 2006年第4期16卷 378-382页

作者： MEI Lin XU Xiaopo CHEN Mingxiu college of urban and environmental sciences Northeast Normal University Changchun 130024 China college of Humanities and sciences Northeast Normal University Changchun 130117 China

northeast China, as the most important production base of agriculture, forestry, and livestock-breeding as well as the old industrial base in the whole country, has been playin a key role in the construction and development of China＇s economy. However, after the policy of reform and open-up was taken in China. the economic development speed and efficiency ofthis area have turned to be evidently lower than those of coastal area and the national average level as well, which is so-called ＇northeast Phenomenon＇ and ＇Neo-northeast Phenomenon＇. In terms of those phenomena, this paper firstly reviews the spatial and temporal features of the regional evolution of this area so as to unveil the profound forming causes of ＇northeast Phenomena＇ and ＇Neo-northeast Phenomena＇. And then the paper makes a further exploration into the status quo of this region and its forming causes by analyzing its economy gross, industrial structure, product structure, regional eco-categories, etc. At the end of the paper, the authors put forward the basic coordinated development strategies for northeast China. namely we can revitalize this area by means of adjustment of economic structure, regional coordination, planning urban and rural areas as a whole, institutional innovation, etc.

关键词： regional evolution spatial-temporal feature coordinated development strategy northeast China

Study on the hyperspectral polarized reflection characteristics of oil slicks on sea surfaces

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Chinese Science Bulletin 2011年第15期56卷 1596-1602页

作者： SUN ZhongQiu ZHAO YunSheng YAN GuoQian LI ShaoPing college of urban and environmental sciences Northeast Normal University Changchun 130024 China

This study is concerned with the need for remote sensing techniques for the monitoring of oil-slick pollution on sea surfaces and the effects of oil-slick pollution on the *** used Daqing crude oil,Jilin crude oil,heavy oil and seawater from Dalian Bay to simulate oil-slick pollution on the sea surface and obtained multi-angle hyperspectral polarized reflectance information,from which we calculated the polarization for different kinds of crude oil,and oil-slicks of different *** comparing the degree of polarization between oil-slicks of different thickness,and sea water,it was found that in the case of thin oil-slicks,the degree of polarization of seawater is higher than that of oil slicks with wavelengths of between 400-1000 ***,there was little difference at a wavelength of 785 *** angles of incident of 20° and 30° (the viewing angle equals the incident angle),it was easy to distinguish the changes of oil-slick thickness by the degree of polarization at 785 and 880 nm in the near-infrared *** crude oil showed its inherent polarized characteristic as the oil-slick thickness increased to a certain *** is to say,the polarization of the seawater was higher than that of the oil-slick in the visible light range,but less than that in the near-infrared *** the incident angle changed from 40° to 50°,the degree of polarization of seawater increased,and it was higher than that for the oil-sick between wavelengths of 400-1000 nm at an angle of incidence of 50°.This research on the polarized characteristics of an oil-slick on a sea surface brings new scientific techniques to the monitoring of sea-surface pollution by remote sensing.

关键词：偏振反射海洋表面高光谱浮油反射特性近红外波段大庆原油遥感技术

Improvement of the determination of hydrogen content in a multicomponent sample by D-T generator

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Chinese Physics C 2010年第5期34卷 606-609页

作者：程道文谷德山刘林茂贾福全李向龙 college of urban and environmental sciences of northeast normal university Radiation Technology Institute of northeast normal university School of Basic sciences Changchun University of Technology

If a D T generator is used as a neutron source to simultaneously measure the content of carbon, hydrogen and oxygen in a multicomponent sample by NIPGA （Neutron Induced Prompt Gamma-ray Analysis）, the 14 MeV neutron flux can be regarded as a constant value. The relationship between the production of the hydrogen characteristic gamma-rays and its content is nonlinear. In this paper, we use MCNP （Monte Carlo N-Particle Transport code） to simulate the relationship and analyze it. In practical measurement of the characteristic gamma-ray, it＇s impossible to get the net count. Therefore, we use the experiment to obtain the relationship between the hydrogen content and the total count of its characteristic gamma-rays. If we use the relationship combined with the simulation result to calculate the hydrogen content, the metrical precision can be much increased. The deviation of hydrogen content between NIPGA and chemical analysis is less than 0.25%, which meets the requirement of coal industry.

关键词： NIPGA hydrogen content D-T neutron generator MCNP nonlinear

Trimetallic mesoporous PdCuRu for efficient formate electrosynthesis from polyethylene terephthalate recycling

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Science China Chemistry 2025年

作者： Yuting Li Huiqin Yao Lizhi Sun Shu Han Xiaoxiang Xu Guangyin Fan Ben Liu college of Chemistry and Materials Science Sichuan Normal University Key Laboratory of Green Chemistry and Technology of Ministry of Education College of Chemistry Sichuan University School of Basic Medical sciences Ningxia Medical University Department of Otorhinolaryngology-Head and Neck Surgery Zhongnan Hospital of Wuhan University

Electrochemical recycling of waste polyethylene terephthalate（PET） plastics represents a green and sustainable route to produce valuable fuels and address serious environmental issues. Despite some encouraged achievements, their progress is still slower because of the lack of highly active and selective electrocatalysts. Here, we reported an efficient PET recycling route with trimetallic PdCuRu mesoporous nanospheres（MSs） as a high-performance electrocatalyst that achieved selective electrosynthesis of valuable formate from PET hydrolysate（PETH） electrooxidation. Penetrated metal mesopores and trimetallic compositions of PdCuRu MSs synergistically optimized electronic structures of Pd sites and changed chemisorption properties of intermediates, which disclosed a high formate Faradic efficiency of 97% and impressive yield rate of 0.49 mmol h-1cm-2in an alkaline solution. Meanwhile, this electrocatalyst held good electrocatalytic stability, retaining high formate Faradic efficiency and yield rate even being performed for 10 cycles, which highlighted its potential applications for practical PET recycling. Our study provides a powerful strategy for designing high-performance electrocatalysts toward selective electro-synthesis of valuable fuels from various waste plastics.

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Characteristics of phytoliths in Leymus chinensis from different habitats on the Songnen Plain in northeast China and their environmental implications

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Science China Earth sciences 2010年第7期53卷 984-992页

作者： JIE DongMei LIU ZhaoYang SHI LianXuan LIU HongMei GE Yong college of urban and environmental Science Northeast Normal UniversityChangchun 130024China School of Life sciences Northeast Normal UniversityChangchun 130024China

The characteristics of phytoliths in Leymus chinensis leaves from five different pH-value habitats from Songnen Plain in China were analyzed to reveal their environmental implications and possible use for quantitative reconstruction of the paleoenvironment. The phytoliths in leaves of L. chinensis from the five habitats showed a non-linear correlation with soil pH. The main types of phytoliths from the different habitats were exactly the same, including silicified stomata, hat-shaped, lanceolate, elongated, multilateral-plate, and tooth-shaped. However, there were significant differences in the contents of each shape of phytoliths among the five habitats. The amount and the volume of weakly tooth-shaped, lanceolate phytoliths and silicified stomata increased with increased pH, while the total amount of phytoliths was reduced. In addition, there were different types of phytoliths in the L. chinensis leaves from the five habitats of different pH, suggesting that the types of phytoliths were controlled, at least in part, by soil pH. The changes of size and percentage of phytoliths were most remarkable at pH 10.15–10.18, indicating that this is the highest pH value that L. chinensis can tolerate.

关键词： phytolith pH habitat Leymus chinensis Songnen Plain environmental implications

Vegetation Change of Ecotone in West of northeast China Plain Using Time-series Remote Sensing Data

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Chinese Geographical Science 2010年第2期20卷 167-175页

作者： HUANG Fang WANG Ping School of urban and environmental sciences Northeast Normal University Changchun 130024 China

Multi-temporal series of satellite SPOT-VEGETATION normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) data from 1998 to 2007 were used for analyzing vegetation change of the ecotone in the west of the northeast China Plain. The yearly and monthly maximal values,anomalies and change rates of NDVI and NDWI were calculated to reveal the interannual and seasonal changes in vegetation cover and vegetation water content. Linear regression method was adopted to characterize the trends in vegetation change. The yearly maximal NDVI decreased from 0.41 in 1998 to 0.37 in 2007,implying the decreasing trend of vegetation activity. There was a significant decrease of maximal NDVI in spring and summer over the study period,while an increase trend was observed in autumn. The vegetation-improved regions and vegetation-degraded regions occupied 17.03% and 20.30% of the study area,respectively. The maximal NDWI over growing season dropped by 0.027 in 1998–2007,and about 15.15% of the study area showed a decreasing trend of water content. Vegetation water stress in autumn was better than that in spring. Vegetation cover and water content variations were sensitive to annual precipitation,autumn precipitation and summer temperature. The vegetation degradation trend in this ecotone might be induced by the warm-drying climate especially continuous spring and summer drought in the recent ten years.

关键词： vegetation change normalized difference vegetation index (NDVI) normalized difference water index (NDWI) SPOT-VEGETATION ecotone northeast China Plain

Spatio-temporal Variation of Landscape Heterogeneity under Influence of Human Activities in Xiamen City of China in Recent Decade

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Chinese Geographical Science 2013年第2期23卷 227-236页

作者： HUANG Yixiong YIN Xiuqin YE Gongfu LIN Jiemin HUANG Ru WANG Na WANG Liang SUN Yue college of urban and environmental sciences Northeast Normal University college of Geographical sciences Fujian Normal University Fujian Academy of Forestry sciences Quanzhou Land and Resources Bureau

Xiamen is an economically competitive and highly urbanized city along the coastal area of Fujian Province, China. The research on spatio-temporal variation of landscape heterogeneity under the influence of human activities is of great importance to the further study on the relationship of landscape pattern and ecological process. It is also crucial to the discovery of spatial variation and intensity distribution of human activities. The research analyzed the intensity of human impacts and the spatial variation features and dynamics of landscape patterns by introducing statistical theories and approaches. We analyzed spatio-temporal variation of landscape heterogeneity using the geostatistical techniques, such as semivariogram and Kriging *** show that there is a higher correlation between landscape heterogeneity indexes and human impact index. Both the indexes show a moderate spatial autocorrelation as well as an obvious characteristic of anisotropy. From 1998 to 2008, the spatial differentiation of the changes in the intensity of human activities and the changes in landscape heterogeneity shows that the landscape patterns in Xiamen are closely related with the urban land utilization methods, the condition of traffic and geographical location and the physical geographical condition such as the terrain and the ecological environment. The process of urbanization has a significant impact on the urban landscape pattern.

关键词： landscape heterogeneity human impact index human activities Xiamen City

Relationship Between Social Economic Agglomeration and Labor Productivity of Core Cities in northeast China

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Chinese Geographical Science 2012年第2期22卷 221-231页

作者： ZHANG Peng YANG Qingshan ZHAO Yichun School of urban and environmental sciences Northeast Normal UniversityChangchun 130024China

Dalian, Shenyang, Changchun and Harbin are the four core cities which play an essential role in terms of promoting the economic development in northeast China. In this paper, the impact of urban agglomeration on labor productivity is explored by making comparisons among these four cities. The model used for analysis is a classical model derived from previous studies. Some indicators, such as population density and economic density, were selected to examine the impact of urban agglomeration on the labor productivity based on the time-series data for the four cities from 1990 to 2007. The four main conclusions are： l） The promotion from the growth rate of population density on the growth rate of labor productivity is limited. 2） The negative relationship exists between the growth rate of employment density and the growth rate of labor productivity. 3） Agglomeration effect exists in the four cities, the highest one is Dalian, Shenyang takes the second place, followed by Changchun and Harbin, and the predominant promotion exerted on the labor productivity is the output density.

关键词： social economic agglomeration labor productivity population density economic density northeast China