Tree architecture is an important component of forest community dynamics - taller trees with larger crowns often outcompete their neighbors, but they are generally at higher risk of wind-induced damage. Yet, we know little about wind impacts on tree architecture in natural forest settings, especially in complex tropical forests. Here, we use airborne light detection and ranging (LiDAR) and 30 yr of forest inventory data in Puerto Rico to ask whether and how chronic winds alter tree architecture. We randomly sampled 124 canopy individuals of four dominant tree species (n = 22-39). For each individual, we measured slenderness (height/stem diameter) and crown area (m2) and evaluated whether exposure to chronic winds impacted architecture after accounting for topography (curvature, elevation, slope, and soil wetness) and neighborhood variables (crowding and previous hurricane damage). We then estimated the mechanical wind vulnerability of trees. Three of four species grew significantly shorter (2-4 m) and had smaller crown areas in sites exposed to chronic winds. A short-lived pioneer species, by contrast, showed no evidence of wind-induced changes. We found that three species' architectural acclimation to chronic winds resulted in reduced vulnerability. Our findings demonstrate that exposure to chronic, nonstorm winds can lead to architectural changes in tropical trees, reducing height and crown areas. La arquitectura de los & aacute;rboles es un componente importante de la din & aacute;mica de la comunidad forestal: los & aacute;rboles m & aacute;s altos con copas m & aacute;s grandes suelen sobrepasar a sus vecinos, pero por lo general corren m & aacute;s riesgo de sufrir da & ntilde;os inducidos por el viento. Sin embargo, es poco lo que se sabe sobre el impacto del viento en la arquitectura de los & aacute;rboles en entornos forestales naturales, sobre todo en bosques tropicales complejos. En este caso, utilizamos LiDAR y 30 a & ntilde;os de datos de campo en Puerto Rico para preguntarnos si los vientos cr & oacute;nicos alteran la arquitectura de los & aacute;rboles. Se tom & oacute; una muestra aleatoria de 124 individuos del dosel de cuatro especies arb & oacute;reas dominantes (n = 22-39). De cada individuo, medimos la esbeltez (altura/di & aacute;metro) y el & aacute;rea de la copa (m2) y evaluamos si la exposici & oacute;n a vientos cr & oacute;nicos influ & iacute;a en la arquitectura teniendo en cuenta la topograf & iacute;a (curvatura, elevaci & oacute;n, pendiente, humedad del suelo) y las variables del vecindario (aglomeraci & oacute;n y da & ntilde;os previos por huracanes). Luego, estimamos la vulnerabilidad mec & aacute;nica de los & aacute;rboles al viento. En los lugares expuestos a vientos cr & oacute;nicos, tres de las cuatro especies crecieron mucho menos (2-4 m) y tuvieron & aacute;reas de copa m & aacute;s peque & ntilde;as. Cecropia schreberiana, en cambio, no mostr & oacute; indicios de cambios inducidos por el viento. La aclimataci & oacute;n arquitect & oacute;nica de tres especies a los vientos cr & oacute;nicos llevaba a una reducci & oacute;n de la vulnerabilidad. Nuestros hallazgos demuestran que la exposici & oacute;n a vientos cr & oacute;nicos puede provocar cambios arquitect & oacute;nicos en los & aacute;rboles tropicales, reduciendo su altura y la superficie de sus copas.

在研究冻土时，经常需要进行大量的数据收集工作，图线能清晰展现数据分布特点，在冻土发育研究中具有重要意义。利用Excel处理和绘制数据，能有效减少人为误差，提高工作效率，更好地满足科研需求。通过筛选处理哈尔滨黑龙江大学寒区地下水研究所的寒区低温地温自动检测装置所监测得到的数据，在该研究中，采用Microsoft Office Excel软件绘制了冻土发育过程线，并对2023年11月29日至2024年4月2日研究区域内全阶段的冻土发育过程进行了深入分析。

在研究冻土时，经常需要进行大量的数据收集工作，图线能清晰展现数据分布特点，在冻土发育研究中具有重要意义。利用Excel处理和绘制数据，能有效减少人为误差，提高工作效率，更好地满足科研需求。通过筛选处理哈尔滨黑龙江大学寒区地下水研究所的寒区低温地温自动检测装置所监测得到的数据，在该研究中，采用Microsoft Office Excel软件绘制了冻土发育过程线，并对2023年11月29日至2024年4月2日研究区域内全阶段的冻土发育过程进行了深入分析。

在研究冻土时，经常需要进行大量的数据收集工作，图线能清晰展现数据分布特点，在冻土发育研究中具有重要意义。利用Excel处理和绘制数据，能有效减少人为误差，提高工作效率，更好地满足科研需求。通过筛选处理哈尔滨黑龙江大学寒区地下水研究所的寒区低温地温自动检测装置所监测得到的数据，在该研究中，采用Microsoft Office Excel软件绘制了冻土发育过程线，并对2023年11月29日至2024年4月2日研究区域内全阶段的冻土发育过程进行了深入分析。

Urbanization impacts plant-herbivore interactions, which are crucial for ecosystem functions such as carbon sequestration and nutrient cycling. While some studies have reported reductions in insect herbivory in urban areas (relative to rural or natural forests), this trend is not consistent and the underlying causes for such variation remain unclear. We conducted a continental-scale study on insect herbivory along urbanization gradients for three European tree species: Quercus robur, Tilia cordata, and Fraxinus excelsior, and further investigated their biotic and abiotic correlates to get at mechanisms. To this end, we quantified insect leaf herbivory and foliar secondary metabolites (phenolics, terpenoids, alkaloids) for 176 trees across eight European cities. Additionally, we collected data on microclimate (air temperature) and soil characteristics (pH, carbon, nutrients) to test for abiotic correlates of urbanization effects directly or indirectly (through changes in plant secondary chemistry) linked to herbivory. Our results showed that urbanization was negatively associated with herbivory for Q. robur and F. excelsior, , but not for T. cordata. . In addition, urbanization was positively associated with secondary metabolite concentrations, but only for Q. robur. . Urbanization was positively associated with air temperature for Q. robur and F. excelsior, , and negatively with soil nutrients (magnesium) in the case of F. excelsior, , but these abiotic variables were not associated with herbivory. Contrary to expectations, we found no evidence for indirect effects of abiotic factors via plant defences on herbivory for either Q. robur or F. excelsior. . Additional biotic or abiotic drivers must therefore be accounted for to explain observed urbanization gradients in herbivory and their interspecific variation.

Since 2002, ash dieback caused by the invasive fungus Hymenoscyphus fraxineus has been observed in Germany. The pathogen and its associated symptoms have fatal consequences for the vitality and survival of European ash (Fraxinus excelsior L.), an economically and ecologically important tree species. This study analyses the ash monitoring results of eleven intensive monitoring plots of the FraxForFuture research network distributed across Germany and focuses on within-stand differences of symptoms in dependence of small-scale site and tree properties. A cohort of 1365 ash trees was surveyed six times over three years, testing and applying a summer and a winter version of a nationally standardised ash dieback assessment key. The main disease symptoms (crown dieback and basal lesions) were more pronounced in areas with higher ash density, in edaphically moist areas (hydromorphic soils), on younger/smaller ash trees, and generally increased over time. However, the trend over time differed between single plots. In case of considering only the surviving part of the ash populations, crown condition even improved in 6/11 plots, indicating a selection process. Large basal lesions at the beginning of the observation period were a very good predictor for deadfall probability, especially on trees with lower stem diameter. Generally, ash dieback related symptoms at stem and crown were highly correlated. Silvicultural management practice in the past that actively pushed ash towards the moister end of its water demand spectrum has to be questioned in the light of ash dieback. Cost-intensive ash re-cultivation in the future-possibly with less dieback-susceptible progenies-should avoid pure ash stands and hydromorphic soil conditions.

对冻土研究时常常会收集大量数据,由于图线具有可以清晰地呈现出数据分布的特点,因此在冻土发育研究中有着重要意义。而采用Excel表格处理数据和作图时,可以减少人为处理数据造成的误差,将工作交给计算机必将提高工作效率,更好满足科研要求。本文选取大兴安岭松岭区为研究区域,利用Microsoft office Excel2019软件生成大兴安岭地区松岭区冻土发育过程线,并对研究区域内2019年11月2日至2020年5月29日冻土发育的全部阶段进行分析。

影响冻土力学性能的因素包括含水量、温度以及加载速率等,且因素间可能存在较强的交互作用。为了区分各因素对冻土力学性能影响的主次以及评估因素间的交互作用,利用Excel软件强大的数理统计功能和良好的可视化界面,制作了能自动分析各因素主次性和交互作用的数据分析模板,从而实现了设计与数据分析的动态可视化。该模板可以用来处理考虑交互作用的3因素3水平试验数据。通过该模板,不但能够节省计算工作量,而且能方便找出影响试验指标的主要因素,并能方便地得出交互作用效应。