Linking intra-seasonal variations in climate and tree-ring δC: A functional modelling approach

Stable carbon isotopic composition (δ¹³C) in tree rings is a widely recognized tool for climate reconstruction, and several works suggest that seasonal information can be extracted from intra-ring δ¹³C variations. In this study, we explored the link between climate and intra-seasonal oak ring δ¹³C using a process-based modelling approach. The ISOCASTANEA model was developed to compute the seasonal dynamics of tree-ring δ¹³C for deciduous species from half-hourly climatic data by accounting for photosynthetic discrimination and carbon translocation and allocation at the tree scale and in tree rings.The model was applied from March 2005 to December 2007 in a 150-year-old deciduous oak forest. Canopy photosynthesis and stomatal conductance were calibrated using H₂O and CO₂ fluxes measured by the eddy flux technique, and simulated δ¹³C values were compared to seasonal patterns of total organic matter δ¹³C measured in tree rings for 2006 and 2007 at the same site. With the inclusion of carbon translocation and with regard to ¹³C enrichment of starch compared to soluble sugars, the model can reasonably simulate the intra-seasonal and inter-annual variability of tree-ring δ¹³C using the same parameter values for 2006 and 2007. The amplitude of the seasonal carbon isotope pattern in tree rings was influenced by both photosynthetic and post-photosynthetic processes (starch enrichment and reserve use). The δ¹³C variations in the early part of the ring, i.e., mainly in the earlywood, were related mostly to carbohydrate metabolism, although diluted information about environmental conditions during the previous year could also be found. The last part of the ring, consisting mainly of latewood, was found to be a good recorder of current-year environmental conditions, in particular relative humidity, at a fine temporal resolution when the growth rate was high. The sensitivity of the δ¹³C in the early part of the ring to carbohydrate metabolism suggests that intra-ring δ¹³C could be used to explore the relationship between tree decline or mortality and carbohydrate deficiency.     

High-resolution inventory of NO emissions from agricultural soils over the Ile-de-France region

Arable soils are a significant source of nitric oxide (NO), a precursor of tropospheric ozone, and thereby contribute to ozone pollution. However, their actual impact on ozone formation is strongly related to their spatial and temporal emission patterns, which warrant high-resolution estimates.Here, we combined an agro-ecosystem model and geo-referenced databases to map these sources over the 12 000 km² administrative region surrounding Paris, France, with a kilometric level resolution. The six most frequent arable crop species were simulated, with emission rates ranging from 1.4 kg N-NO ha⁻¹ yr⁻¹ to 11.1 kg N-NO ha⁻¹ yr⁻¹. The overall emission factor for fertilizer-derived NO emissions was 1.7%, while background emissions contributed half of the total NO efflux. Emissions were strongly seasonal, being highest in spring due to fertilizer inputs. They were mostly sensitive to soil type, crops' growing season and fertilizer N rates.     

The Contribution of Habitat Loss to Changes in Body Size, Allometry, and Bilateral Asymmetry in Two Eleutherodactylus Frogs from Puerto Rico

Abstract:  Amphibian populations have been declining worldwide and the exact mechanisms underlying these changes are not well understood. We examined environmentally induced phenotypic changes that may reflect ongoing stresses on individuals and therefore their ability to persist in increasingly changing landscapes. Specifically, we evaluated the contribution of habitat loss on the size, allometry, and levels of fluctuating asymmetry of Eleutherodactylus antillensis and E. coqui , 2 common species that are endemic to Puerto Rico. We x-rayed frogs collected at 9 sites that differed in the amount of forest cover and measured their snout-vent, radio-ulna, femur, and tibio-fibula lengths. E. antillensis and E. coqui were smaller in the highly disturbed (≤20% forest cover) than in the intermediately (20–70% forest cover) and little-disturbed (≥70% forest cover) landscapes. In E. antillensis but not in E. coqui , the slope and intercept of the curves relating snout-vent length with the length of the 3 bones differed with degree of forest cover, suggesting an effect of habitat loss on body shape. In E. antillensis and E. coqui , differences between right and left sides corresponded to true fluctuating asymmetry; however, only the radio-ulna length of E. coqui showed a trend toward an increase in fluctuating asymmetry with habitat loss. Because body size scales with a variety of physiological, life history, and ecological traits, conservation programs aimed at monitoring morphological changes in amphibians may help in understanding the mechanisms that contribute to their persistence in changing environments.     

Diversity and organizational innovation: The role of employee involvement

This study examined the interactive effects of workplace diversity and employee involvement on organizational innovation. Using a sample of 182 large Canadian organizations, we found a three‐way interaction between level of employee involvement, variation in involvement, and racioethnic diversity on innovation. In organizations with high levels of employee involvement, high variation in involvement was associated with higher involvement levels among racioethnic minorities, resulting in a stronger association between diversity and innovation. Furthermore, the association between White employee involvement and innovation was significantly more positive under the condition of high involvement among racioethnic minority group members. Thus, ensuring high levels of involvement among members of historically marginalized racioethnic groups enhances the innovation effects of employee empowerment systems. Copyright © 2010 John Wiley & Sons, Ltd.     

地区发展差异与湖北省可持续发展战略

湖北省的经济发展水平与全国其它地区存在着较大的差异，从全国范围看，湖北省多年一直处在中等偏下的水平，而在长江流域，近年湖北省一下游省市的差距在迅速扩大；在中心地区各省中，湖北则相对领先。     

Biodiversity Consequences of Genetic Variation in Bark Characteristics within a Foundation Tree Species

Abstract: The developing field of community genetics has the potential to broaden the contribution of genetics to conservation biology by demonstrating that genetic variation within foundation plant species can act to structure associated communities of microorganisms, invertebrates, and vertebrates. We assessed the biodiversity consequences of natural patterns of intraspecific genetic variation within the widely distributed Australian forest tree, Eucalyptus globulus. We assessed genetic variation among geographic races of E. globulus (i.e., provenances, seed zones) in the characteristics of tree‐trunk bark in a 17‐year‐old common garden and the associated response of a dependent macroarthropod community. In total, 180 macroarthropod taxa were identified following a collection from 100 trees of five races. We found substantial genetically based variation within E. globulus in the quantity and type of decorticating bark. In the community of organisms associated with this bark, significant variation existed among trees of different races in composition, and there was a two‐fold difference in species richness (7–14 species) and abundance (22–55 individuals) among races. This community variation was tightly linked with genetically based variation in bark, with 60% of variation in community composition driven by bark characteristics. No detectable correlation was found, however, with neutral molecular markers. These community‐level effects of tree genetics are expected to extend to higher trophic levels because of the extensive use of tree trunks as foraging zones by birds and marsupials. Our results demonstrate the potential biodiversity benefits that may be gained through conservation of intraspecific genetic variation within broadly distributed foundation species. The opportunities for enhancing biodiversity values of forestry and restoration plantings are also highlighted because such planted forests are increasingly becoming the dominant forest type in many areas of the world.     

季节变动预测方法浅析

本文客观分析了普遍存在的季节变动国现象，探寻了季节变动国现象的变化规律，并地一步该规律进行了预测，并提出了切实可行的方法。     

城市不同功能区地表灰尘重金属时空动态变化

以贵阳市交通区-城市广场-文教区-住宅区-城中村地表灰尘为研究对象,对不同月份地表灰尘进行跟踪采样分析,研究不同功能区地表灰尘重金属质量比的时空变化特征,并通过内梅罗指数法对灰尘重金属累积程度进行评价。结果表明:1)As、Cd和Pb月质量比最低值出现在6—7月,而Cu、Ni和Zn月质量比最低值出现在11月上旬,各元素月质量比最高值出现的月份不尽相同,但以11—12月为主;2)春冬季地表灰尘重金属质量比高于夏秋季;3)灰尘中Ni、Zn质量比随时间和区域的变化最小,As、Cd、Cu和Pb质量比随时间和区域的变化较大,这4种元素在城市广场累积最重;4)人类活动是影响地表灰尘重金属迁移和累积的重要因素之一,温度、降雨、街道形状和地理位置也是影响地表灰尘重金属含量的因素。     

Sometimes less is more: Directed coping with interpersonal stressors at work

Within the coping literature, researchers have long been interested in identifying ways in which individuals can improve their coping efforts, making them more effective and thereby reducing the harmful effects of stressful encounters. Although Lazarus and Folkman's transactional model has greatly advanced understanding of the coping process, there continues to be methodological and conceptual challenges that have hindered understanding of the mechanisms behind effective coping. Addressing these issues in the use of a novel approach of analyzing variation in coping (i.e., directed coping) at both the coping event and person coping levels, the current study examined the process of coping with work stress and the beneficial coping outcomes associated with using a directed coping strategy. A total of 143 nurses completed up to 12 weekly surveys online, reporting on weekly stressful interpersonal conflicts and how they coped with them. Results from multilevel analyses supported predictions that greater directed coping at both the level of the coping event and person is associated with improvements in occupational health outcomes even after controlling for other coping factors. Implications of these results are discussed in relation to future research on coping effectiveness and workplace applications. Copyright © 2015 John Wiley & Sons, Ltd.     

基于模糊优选和CRITIC法的电力碳排放权区域初始分配——以华东电网区域为例

为科学、合理分配电力行业碳排放权,文章综合考虑公平、效率和可持续发展原则,构建了电力碳排放权分配体系,并利用CRITIC法确定指标权重,运用模糊优选法计算碳排放权初始分配比例,结果表明:单位地区生产总值电耗是最主要的影响因素,公平原则下的电力碳排放量、电力能源消费总量和火力发电量也是重要的影响因素;碳排放量问题是复杂的系统问题,碳排放权初始分配要综合考虑公平性原则、效率性原则和可持续原则。最后,为达到和谐稳定的碳排放权分配方案,希望在以后的研究中加强和谐型评判与改进方法。