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塔里木河下游阿拉干断面胡杨树高的分布和密度

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生态环境 2008年第3期17卷 1086-1090页

作者：蔡富艳玉米提·哈力克艾尔肯·艾白不拉阿布都米吉提·阿布力克木 bodo coenradie Birgit Kleinschmit 新疆大学资源与环境科学学院新疆乌鲁木齐830046 新疆绿洲生态教育部重点实验室新疆乌鲁木齐830046 塔里木河流域管理局新疆库尔勒841000 中国科学院新疆生态与地理研究所新疆乌鲁木齐830011 德国柏林理工大学景观规划研究所德国柏林10623

通过小尺度生态监测与遥感数据分析获取塔里木河下游胡杨（Populus euphratica Oliv．）林现状信息，将胡杨个体对输水的响应实测数据和QuickBird影像信息进行对比和分析，“面”上宏观调查与“点”上典型研究相结合，集中对塔里木河下... 详细信息

通过小尺度生态监测与遥感数据分析获取塔里木河下游胡杨（Populus euphratica Oliv．）林现状信息，将胡杨个体对输水的响应实测数据和QuickBird影像信息进行对比和分析，“面”上宏观调查与“点”上典型研究相结合，集中对塔里木河下游阿拉干断面设立的100hm2长期监洲样方内的4500棵胡杨树进行了详细的调查。研究表明：胡杨密度随着离河岸距离增加而呈现降低的规律。不同树高的胡杨也呈一定规律分布。树高小于3m的幼树主要分布在距河道50m范围内；树高3-9m之间的胡杨在研究区中占绝对优势；树高大于9m的胡杨在距河道200m内分布比较均匀，200m之外分布稀少。

关键词：塔里木河下游生态输水胡杨树高密度结构

Long-term vegetation development on a wildfire slope in Innerzwain(Styria,Austria)

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Journal of Forestry Research 2014年第1期25卷 103-111页

作者： bodo Malowerschnig Oliver Sass Karl-Franzens-University Graz Department of Geography and Regional Science

Forest fires in mountainous areas can cause severe defores-tation which can potentially trigger secondary natural hazards like debris falls and avalanches. We documented an extreme case study for the range of possible post-fire land cover （LC） dynamics. We investigated a 15-ha, steep （10°-65°） burnt slope in Styria （Austria） at elevation of 760-1130 m, which burned in 1946 and has not fully recovered to date. Seven 8-class legend LC maps were produced （1954, 1966, 1973, 1982, 1998, 2004, 2009） and integrated in a vector-based GIS, mainly by on-screen interpretation of aerial photos. Our aim was to clarify how post-wildfire LC dynamics take place on a severely damaged, steep slope and to give a basic projection of the future vegetation recovery process. The pre-fire Pinus sylvestrisstands have been mainly replaced by Picea abies and Larix decidua. Regeneration proceeded mainly from the base of the slope upwards. All tree species together still cover no more than 40% of the slope after more than 60 years of recovery, while grassland communities and rock/debris areas have expanded. Multitemporal analysis showed a slow but steady increase in woodland cover. Degraded rock/debris areas, however, expanded as well because soil erosion and related debris flows remained active. Slope angle （with a threshold value of approx. 35-40°） seemed to control whether erosion or regeneration prevailed. According to a simple extrapolation, the slope will not reach its former condition before 2070. This extreme disturbance window of more than 120 years is owed to the steepness of the slope and to the shallow soils on dolomitic bedrock that were severely damaged by the fire. The neglect of any game fencing is a further factor slowing regeneration.

关键词： wildfire landcover change temperate forest aerial photos,soil degradation vegetation development

Reactive pathways toward parasitic release of singlet oxygen in metal-air batteries

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npj Computational Materials 2021年第1期7卷 1135-1142页

作者： Adriano Pierini Sergio Brutti Enrico bodo Department of Chemistry University of Rome“La Sapienza”RomeItaly GISEL—Centro di Riferimento Nazionale per i Sistemi di Accumulo Elettrochimico di Energia FirenzeItaly

The superoxide disproportionation reaction is a key step in the chemistry of aprotic metal oxygen batteries that controls the peroxide formation upon discharge and opens the way for singlet oxygen *** we clarify the energy landscape of the disproportionation of superoxide in aprotic media catalyzed by group 1A *** analysis is based on ab initio multireference computational methods and unveils the competition between the expected reactive path leading to peroxide and an unexpected reaction channel that involves the reduction of the alkaline *** channels lead to the release of triplet and singlet O_(2).The existence of this reduction channel not only facilitates singlet oxygen release but leads to a reactive neutral solvated species that can onset parasitic chemistries due to their well-known reducing ***,we show that the application of moderate overpotentials makes both these channels accessible in aprotic batteries.

关键词： properties release singlet

Radial variations in xylem sap flux in a temperate red pine plantation forest

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Ecological Processes 2021年第1期10卷 328-336页

作者： Alanna V.bodo M.Altaf Arain School of Earth Environment and SocietyMcMaster UniversityHamiltonONCanada McMaster Centre for Climate Change HamiltonONCanada

Background:Scaling sap flux measurements to whole-tree water use or stand-level transpiration is often done using measurements conducted at a single point in the sapwood of the tree and has the potential to cause significant *** studies have shown that much of this uncertainty is related to(i)measurement of sapwood area and(ii)variations in sap flow at different depths within the tree ***:This study measured sap flux density at three depth intervals in the sapwood of 88-year-old red pine(Pinus resinosa)trees to more accurately estimate water-use at the tree-and stand-level in a plantation forest near Lake Erie in Southern Ontario,*** showed that most of the water transport(65%)occurred in the outermost sapwood,while only 26%and 9%of water was transported in the middle and innermost depths of sapwood,***:These results suggest that failing to consider radial variations in sap flux density within trees can lead to an overestimation of transpiration by as much as 81%,which may cause large uncertainties in water budgets at the ecosystem and catchment *** study will help to improve our understanding of water use dynamics and reduce uncertainties in sap flow measurements in the temperate pine forest ecosystems in the Great Lakes region and help in protecting these forests in the face of climate change.

关键词： Sap flow Transpiration Water use Red pine Temperate forest Great Lakes region

Effects of variable retention harvesting on canopy transpiration in a red pine plantation forest

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Ecological Processes 2022年第1期11卷 374-385页

作者： Alanna V.bodo M.Altaf Arain School of Earth Environment and SocietyMcMaster University1280 Main Street WestHamiltonON L8S 4K1Canada McMaster Centre for Climate Change McMaster University1280 Main Street WestHamiltonON L8S 4K1Canada

Background:Variable Retention Harvesting(VRH)is a forest management practice applied to enhance forest growth,improve biodiversity,preserve ecosystem function and provide economic revenue from harvested *** are many different forms and compositions in which VRH is applied in forest *** this study,the impacts of four different VRH treatments on transpiration were evaluated in an 83-year-old red pine(Pinus Pinus resinosa)plantation forest in the Great Lakes region in *** VRH treatments included 55%aggregated crown retention(55A),55%dispersed crown retention(55D),33%aggregated crown retention(33A),33%dispersed crown retention(33D)and unharvested control(CN)*** VRH treatments were implemented in 1-ha plots in the winter of 2014,while sap flow measurements were conducted from 2018 to ***:Study results showed that tree-level transpiration was highest among trees in the 55D treatment,followed by 33D,55A,33A and CN *** found that photosynthetically active radiation(PAR)and vapor pressure deficit(VPD)were major controls or drivers of transpiration in all VRH *** study suggests that dispersed or distributed retention of 55%basal area(55D)is the ideal forest management technique to enhance transpiration and forest ***:This study will help researchers,forest managers and decision-makers to improve their understanding of water cycling in forest ecosystem and adopt the best forest management regimes to enhance forest growth,health and resiliency to climate change.

关键词： Variable Retention Harvesting Forest management Transpiration Sap flow Red pine Great Lakes region

Symmetry Adapted Block Diagonalisation in Equivariant Steady State Bifurcation Problems and its Numerical Application

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数学进展 1991年第4期 455-487页

作者： Peter Stork,bodo Werner Institut fur Angewandte Mathematik der Universitat Hamburg Bundesstr.55 D-2000 Hamburg 13 Federal Republic of Germany Institut fur Angewandte Mathematik der Universitat Hamburg Bundesstr.55 D-2000 Hamburg 13 Federal Republic of Germany

Considering steady state bifurcation of single parameter r-equivariant systemswhere Γ is a compact Lie group acting on X via a faithful orthogonal representation, we simultaneously block-diagonalise all jacobians of g along a solution path with respect to symmetry adapted subspaces and apply bifurcation groups to reduce symmetry breaking bifurcation points to simple bifurcation points. In generical situations this algorithm allows for numerically stable use of continuation methods and steady state bifurcation point detection and computation. The large scale decrease of computing efforts is demonstrated at computing the equilibria of a hexagonal lattice dome with 21 degrees of freedom, we present a great variety of solution arcs with symmetry from full D6 down to Z2 symmetry.

关键词： Symmetry Adapted Block Diagonalisation in Equivariant Steady State Bifurcation Problems and its Numerical Application

Quantifying the refractive index dispersion of a pigmented biological tissue using Jamin–Lebedeff interference microscopy

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Light(Science & Applications) 2013年第1期2卷 58-63页

作者： Doekele G Stavenga Hein L Leertouwer bodo D Wilts Computational Physics Zernike Institute for Advanced MaterialsUniversity of GroningenNL-9747 AG GroningenThe Netherlands

Jamin–Lebedeff polarizing interference microscopy is a classical method for determining the refractive index and thickness of transparent ***,we extend the application of this method to pigmented,absorbing biological tissues,based on a theoretical derivation using Jones *** novel method is applied to the wings of the American Rubyspot damselfly,Hetaerina *** membranes in the red-colored parts of the damselfly’s wings,with a thickness of 2.5 μm,contain a pigment with maximal absorption at 490 nm and a peak absorbance coefficient of 0.7 μm^(-1).The high pigment density causes a considerable and anomalous dispersion of the refractive *** result can be quantitatively understood from the pigment absorbance spectrum by applying the Kramers–Kronig dispersion *** of the spectral dependence of the refractive index and the absorption are valuable for gaining quantitative insight into how the material properties of animal tissues influence coloration.

关键词： absorption chitin insect wings Jones calculus Kramers–Kronig relations

Anxiety and depression in adult patients with celiac disease on a gluten-free diet

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World Journal of Gastroenterology 2010年第22期16卷 2780-2787页

作者： Winfried Huser Karl-Heinz Janke bodo Klump Michael Gregor Andreas Hinz Department of Internal Medicine I Klinikum Saarbrücken Winterberg 1 D-66119 Saarbrücken and Department of Psychosomatic Medicine and Psychotherapie Technische Universitt München Baden-Württemberg State Health Office District Government Stuttgart Gastroenterology and Gastrointestinal Cancer St. Anna Hospital Obere Waiblinger Starβe 101 D-70374 Stuttgart Germany and Department of Internal Medicine 1 Universittskliniken Tübingen Department of Internal Medicine 1 Universittskliniken Tübingen Department of Medical Psychology and Medical Sociology Universitt Leipzig

AIM: To compare anxiety and depression levels in adult patients with celiac disease (CD) on a gluten-free diet (GFD) with ***: The levels of anxiety, depression and of a probable anxiety or depressive disorder were assessed by the Hospital Anxiety and Depression Scale in 441 adult patients with CD recruited by the German Celiac Society, in 235 age-and sex-matched patients with inflammatory bowel disease (IBD) in remission or with slight disease activity, and in 441 adult persons of a representative German general population sample (GP). Potential demographic (age, sex, social class, family status) and disease-related (latency to diagnosis, duration of GFD, compliance with GFD, thyroid disease) predictors of anxiety and depression in CD were tested for by regression analyses. RESULTS: The level of anxiety in CD patients was predicted (R 2 = 0.07) by female gender (P = 0.01). Female sex (OR = 3.6, 95% CI: 1.3-9.4, P = 0.01) was associated with a probable anxiety disorder. Living alone (OR = 0.5, 95% CI: 0.2-0.9, P = 0.05) was associated with a reduced risk of an anxiety disorder. The level of depression and a probable depressive disorder were not predicted by any of the demographic and medical variables tested for. The levels of anxiety in patients with CD (6.6 ± 3.4) and with IBD (6.9 ± 3.7) were higher than those of persons in the GP (4.6 ± 3.3) (both P < 0.001). The levels of depression in persons with CD (4.2 ± 3.4), IBD (4.6 ± 3.4) and of the GP (4.2 ± 3.8) did not differ (P = 0.3). The prevalence of a probable anxiety disorder in persons with CD (16.8%) and IBD (14.0%) was higher than that of the GP (5.7%) (P < 0.001). The prevalence of a probable depressive disorder did not differ significantly between the three groups (P = 0.1). CONCLUSION: Anxiety in adult German female celiacs on a GFD is higher than in persons of the GP. Female celiacs on a GFD should be screened for anxiety.

关键词： Celiac disease Anxiety Depression Gender

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吸湿对单向亚麻纤维复合材料力学性能的影响

复合材料学报 2022年第2期39卷 608-616页

作者：贾云龙 FIEDLER bodo 常州工学院航空与机械工程学院/飞行学院常州213032 汉堡工业大学聚合物与复合材料研究所汉堡D21073

为探明亚麻纤维增强树脂复合材料(FFRPs)在长期潮湿环境中的力学性能变化规律,基于真空辅助树脂模塑传递成型(VARTM)手段制备了的干燥状态的单向FFRPs(纤维体积分数为40vol%)。试验研究了FFRPs在30°C、80%相对湿度(RH)环境中放置5天、3... 详细信息

为探明亚麻纤维增强树脂复合材料(FFRPs)在长期潮湿环境中的力学性能变化规律,基于真空辅助树脂模塑传递成型(VARTM)手段制备了的干燥状态的单向FFRPs(纤维体积分数为40vol%)。试验研究了FFRPs在30°C、80%相对湿度(RH)环境中放置5天、35天、86天后拉伸力学性能变化。结果表明,FFRPs在湿热环境中吸水量近似符合一维情况下的Fickian第二定律,饱和吸水量为5.3%左右。FFRPs在垂直于纤维方向上的拉伸强度和模量随吸湿度增加递减,断口微观分析表明吸湿降低了纤维基体界面结合性能。然而,FFRPs在纤维方向上的拉伸强度并未因吸湿降低,反而在吸湿过程呈现出先减小后增加的趋势,此变化规律文献中尚未报道:相比干燥状态,放置5天后拉伸强度下降5.7%;放置35天后拉伸强度增加18.7%;放置86天时样品已处在饱和吸湿状态,拉伸强度略微减小,但仍比干燥状态增加13.7%。FFRPs在纤维取向上拉伸强度变化可解释为多因素共同作用的结果。

关键词：植物纤维复合材料亚麻纤维吸湿拉伸力学性能耐久性