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关键词： Soil nutrient stocks   C:N:P   Forest conversion   Use intensification   Land-use change  

摘要： Natural forests conversion to intensively managed forest plantation is an expanding land-use change that could profoundly impact C and nutrient terrestrial cycles. Here we assessed how different soil types respond to changes in the C, N, and P major biogeochemical pools by comparing paired natural broadleaf deciduous forest and pine plantation across five different soils with contrasting mineralogy. We quantified major biogeochemical stocks in all soil compartments to a depth up to 240 cm, including the forest floor. Our result showed that soils' C, N, and P stocks and stoichiometry do not respond equally to this land-use change. Deep soil biogeochemical pools (120-240 cm) contributed substantially to the total soil stock in most sites (up to 40% for C, 47% for P, and 52% for P). Elemental depth distribution was significantly modified because of forest substitution, and some sites displayed a significant stock reduction in deep soil compartments (>120 cm). Whole mineral soil C and N stocks were generally lower in the planted forest, while these stocks in litter layers were significantly different between soil and forest types (p < 0.001). C and N stocks in soils with low clay content or low activity clays were more significantly affected by forest substitution. On the other hand, soils with moderate to high clay content and dominant high activity clay were only mildly affected by this change. Phosphate and ammonium available pools were more affected in low activity and low clay content soil. P pools, and consequently C:P and N:P ratios in mineral soils, vary significantly between soil types. Our results corroborate that soils with contrasting properties respond differently to native forest substitution to intensively managed plantations and that the magnitude of this response seems to be controlled mostly by clay mineralogy.

关键词： Eco-innovation   Stock returns   Innovation type  

摘要： Purpose The purpose of this paper is to determine the role of eco-innovation type and its degree of novelty in increasing the stock returns of technology-based knowledge-intensive business service companies (T-KIBS), to advance the development of the concept of eco-innovation within the literature on the effects of innovation. Design/methodology/approach The effects of four eco-innovation types were examined across three degrees of novelty involved. The event study methodology was applied to the sample of 238 eco-innovation announcements released during the period of January 2016-June 2019 (inclusive) by European T-KIBS. Findings While the implementation of product and organisational eco-innovation was the most beneficial, the results indicated that a high degree of novelty resulted in larger increase of stock returns in the case of all the four eco-innovation types. Research limitations/implications The eco-innovation announcements were gathered from specialised databases. However, it could be the case that companies may have used different communication channels (e.g. social media) to communicate innovation. Furthermore, a certain amount of bias undoubtedly exists, as the data came only from the European Union. Expanding the spatial scope to include the North American (especially the USA) and Asian economies appears necessary. Practical implications The practical insights into the role that the degree of novelty plays in eco-innovation announcements were formulated, which may be used to increase the market valuation of the firm. Social implications Strategies supporting eco-innovation are crucial for business development as the value created for the stakeholders involved transmits in time into the enterprise value. Originality/value The paper attempts to fill the research gap concerning the impact of eco-innovation on the stock returns of T-KIBS.

关键词： 稀土行业   北方稀土   财务分析   估值分析  

摘要： 改革开放以来,中国稀土工业迅速发展,导致稀土行业股票受到追捧。为了使投资者掌握股票的投资价值分析方法,本文以北方稀土为研究标的,进行投资价值分析。首先,对我国宏观经济形势和稀土行业进行分析。其次进行企业分析,分析北方稀土所具有的竞争优势。然后进行财务分析,北方稀土的偿债能力和营运能力较强,盈利能力良好,总体上财务水平良好。最后分别使用市盈率法、市净率法和剩余收益估值模型对北方稀土进行估值,得出股票的内在价值。将股票的内在价值与其市值做比较,最后得出北方稀土的股票具有投资价值,给投资者提供投资参考。

关键词： 现值计量   经济本质   预期信用减值模型  

摘要： 资产减值作为对历史成本的修正手段,在一定的程度上起到了修正资产的账面价值与市场价值背离的效果。本文分别讨论了预期信用损失模型第一、第二阶段的资产减值计提中,采用静态的现值计量和动态现值计量会有不同经济后果:采用静态现值计量的结果是资产真实的价值与计量结果相互背离;采用动态现值计量的结果是资产真实的价值与计量结果相互融合。基于在信息不对称的情况下,计提资产价值准备有可能沦为管理层进行损益调整的工具,因此本文建议:在预期信用损失模型三阶段估计中,完全采用动态的现值计量,对第一、第二阶段进行追溯调整,使资产的经济价值与预期现金流的现值完全匹配。

关键词： Fisheries management   Stakeholder objectives   Decision analysis   Stock assessment  

摘要： Prioritising fished stocks for monitoring and assessment is a challenge for management of resource-limited fisheries. We developed a participatory multi-criteria decision analysis (MCDA) to prioritise 141 fished stocks in New South Wales (NSW), Australia, based on their importance to fisheries management. The approach aimed to: (1) structure the decision problem, (2) force consideration of management objectives at the stock level, (3) balance trade-offs generated by competing objectives, and (4) balance differences in the perceived importance of objectives among fisheries managers. Performance scores and criteria weightings for ten management objectives were elicited from two groups of managers (commercial and recreational), combined into a total performance value for each stock, and ordered to infer priority for assessment. Stocks with higher total performance values typically had an exploitation status of Overfished, Growth-overfished, or Uncertain and were subject to a catch quota, because these criteria were weighted highly by both management groups. However, total performance was more sensitive to differences in weightings between management groups than to variations in relative magnitude of weightings among criteria. The priority list of stocks will assist decisions regarding the optimal allocation of resources for fisheries research in NSW. This MCDA approach is adaptive and can incorporate changes in management priorities through time and additional ecosystem components.

关键词： 减值测试   资产减值   企业财务报表   会计实务   未来现金流量的现值   公允价值   预计未来现金流量现值   减值迹象  

摘要： 在会计实务中,经常会遇到资产出现减值迹象需要进行减值测试的情形,减值测试过程中一般会采取估计资产的公允价值减去处置费用后的净额方法(简称"方法一")或者估计资产预计未来现金流量的现值的方法(简称"方法二")。选择不同的减值测试方法,减值测试结果可能会出现重大差异的情形,对企业财务报表产生重大影响。

关键词： Soil organic carbon   Soil total nitrogen   Altitude   Mountainous region   Vegetation zones  

摘要： The soil organic carbon (SOC) and nitrogen (N) in the Yunnan Province, southwestern China, is related to the complex topography and multiple vegetation zones. However, the variation in SOC and total nitrogen (TN) stocks under different vegetation types and altitudes in the mountainous regions in Yunnan is still unknown. This study aimed to investigate the spatial distribution of SOC and TN stocks affected by different vegetation types and altitudes within three soil depths (0-20 cm, 20-40 cm, and 40-60 cm) and to determine the factors controlling the SOC and TN stocks across the mountainous regions in western Yunnan. Nine vegetation types, including tropical rainforest (TR), tropical monsoon forest (TM), broad-leaved evergreen forest (BLE), evergreen coniferous and broad-leaved mixed forest (ECB), broadleaved deciduous forest (BLD), coniferous forest (CF), alpine shrub meadow (ASM), dark coniferous forest (DC) and alpine meadow (AM), along with an altitude gradient (600-4500 m), were selected. The results showed that the SOC and TN contents decreased with increasing soil depth in most vegetation types, except DC. Soils under different vegetation types with pH ranging from 3.25 to 3.74 and 5.10 to 6.68 had significantly higher SOC stocks than soils with pH ranging from 3.99 to 5.09 (P < 0.05). The SOC and TN stocks were positively correlated with the mean annual temperature and mean annual precipitation. Higher SOC stocks (64.01-139.88 Mg ha(-1)) and TN stocks (23.42-49.36 Mg ha(-1)) were observed in CF, ASM, DC and AM with higher altitudes (3600-4500 m) than other vegetation types with lower altitudes (600-3600 m). The significant linear relationship between SOC and TN stocks (P < 0.01) demonstrated that most of the variations in TN are related to the changes in SOC storage, and the accumulation of SOC could influence TN stocks. Our results also suggest that vegetation type, altitude and pH could be the major factors controlling the spatial distribution of SOC and T

关键词： ESG   股票收益率   Fama-French三因子   固定效应模型  

摘要： 当前降低企业环境污染水平、践行社会责任、提高治理能力已成为社会各界大力倡导的方向。如何引导市场加大对绿色环保产业的投入,以及如何让企业自觉提升可持续发展能力,已成为社会主义市场经济下生态文明建设的重要课题。我国的ESG体系建设起步较晚,ESG在我国金融市场中还是一个新兴理念。尽管国内关于ESG与财务绩效之间的关系研究已经开始,但针对ESG表现与股票收益关系的研究并不多。鉴于此,本文借鉴了国外学者的研究方法对企业ESG表现和股票收益率之间的关系进行了研究。首先,依据企业ESG评级构建了四个投资组合,接着采用了CAPM模型和Fama-French三因子模型对ESG投资组合的超额收益进行检测。然后通过固定效应面板回归模型对企业ESG表现和投资组合收益率之间的关系进行实证检验,最后,对企业ESG变化的股票投资收益预测能力进行了检测。CAPM模型的实证结果表明高评级的投资组合存在明显的超额收益,最高评级投资组合与最低评级组合的Jensen’sα显著不同,且高评级投资组合的β值在1%水平显著小于1,低评级投资组合的β在1%水平显著大于1。Fama-French三因子的实证结果与CAPM的实证结果基本保持一致。同时,加入ESG变量的面板回归结果也表明ESG变量在1%水平下对投资组合的平均月回报率有影响,且通过了稳健性检验。而企业ESG变化预测股票投资收益的实证结果表明:保持其他条件不变,虽然当期企业ESG的变化对于下一期和长期的收益预测能力不够,但当期企业ESG评分上升对于中期收益的影响是显著的。

关键词： 避税   企业价值   股票流动性   资本市场  

摘要： 随着市场经济的不断完善,学术界对企业价值的研究逐渐深入,企业实施避税及纳税筹划安排是否能真正提高企业价值?学术界对此争议不断。本文以此为切入点,结合委托代理等理论,采用上市公司最新数据,探讨现阶段避税与企业价值的关系。另外,作为上市公司的主要战场,资本市场近年来蓬勃发展,对企业尤其是上市企业影响逐渐加深,本文尝试从资本市场视角出发,研究股票流动性对避税与企业价值二者关系的调节机制.本文共分为六章,第一章为引言。第二章为文献综述,首先对国内外文献中避税与企业价值关系的研究情况进行了归纳总结,其次对股票流动性的作用情况进行了梳理。第三章在信息不对称及股票流动性等理论分析的基础上,提出本文的两个假设,假设一,企业避税对企业价值存在显著负向影响;假设二,股票流动性的提高能够缓解企业避税对企业价值的负向影响。第四章为模型的研究和设计,首先搜集和梳理上市公司最新数据,形成以2009-2019年A股上市公司为样本的面板数据;其次构建计量模型。为研究避税与企业价值的关系,以实际税率为被解释变量、tobinq系数为解释变量构建基准模型;为研究股票流动性对二者关系的调节作用,在基准模型的基础上引入股票流动性以及其与实际税率的交互项,构建机制检验分析模型。第五章首先依据豪斯曼检验结果,对模型进行固定效应回归分析;其次为深入探讨避税对企业价值的作用机理,根据企业的产权性质、行业以及杠杆对全样本进行了异质性分组讨论;最后为了检验结果的稳健性,更换避税指标、进行异质性分组检验以及内生性检验,实证结果显示基准回归和机制检验回归模型均稳健。第六章在综合考虑理论分析和实证检验结果后,得出如下研究结论:上市公司避税程度越高,企业价值越低;股票流动性的提高能够缓解避税行为对企业价值的负向影响。本文在研究过程中,创新性地引入了股票流动性变量。当前,尚没有文献将股票流动性的调节作用引入企业价值研究。股票流动性作为资本市场的重要属性,可以影响股东发挥监督治理作用的效果,反映股价信息含量,调节企业信息不对称与信息透明度。因此本文将资本市场表现与企业行为相联系,为企业纳税决策和避税决策提供了参考依据,丰富了企业避税的研究体系,具有一定的学术价值和现实意义。

关键词： 企业声誉   股票回购   市场反应   信号传递  

摘要： 股票回购是指上市公司从股票市场上购回一定量本公司股票的行为，最早出现在上世纪50年代的美国，并且逐渐成为一种常见的上市公司进行资本运作的手段。股票回购在我国的起步比较晚，早期对股票回购的限制也较多，但是随着我国资本市场的不断发展以及近年来中美贸易摩擦和国内经济转型的双重刺激，国家逐渐对股票回购采取支持的态度，尤其是2018年新的回购政策落地，极大地激发了企业进行股票回购的热情，回购数量和规模不断创出新高。　　已有研究表明股票回购作为一种典型的空谈博弈，其公告价值效应受到公司资产结构如资产负债率、账面市值比以及回购规模和回购时机等因素的影响，但是鲜有学者从企业声誉的角度来考虑这个问题。随着股票回购数量的增加，公开市场股票回购的非强制执行会导致公告的信号效应越来越弱，而企业声誉作为企业重要的无形资产，是投资者信任程度的重要依据，会影响投资者的投资决策。因此本文将企业声誉引入股票回购研究，以期填补相关研究的空白。　　本文选取2011年1月至2019年12月的350起公开市场股票回购事件为样本，将企业声誉分为大小和好坏两个维度，利用股吧股民的关注度衡量企业声誉的大小，媒体报道的倾向衡量企业声誉的好坏，依托事件研究法和多元回归模型进行了实证研究。结果表明，声誉越大的企业，回购公告价值效应越好;声誉越好的企业，回购公告价值效应越差;声誉较大的企业在实际回购过程中会利用自己的声誉优势，倾向于回购更少数量的股票。此外，在回购公告中明确说明回购目的是提升股价的企业，会得到市场更积极的反应。在此基础上，本文还利用分析师关注度作为企业声誉大小的代理变量，换用不同的模型等方式进行了稳健性检验，获得了一致性的结论。最后，本文从监管机构、上市公司和投资者三个角度给出了相关建议。