Use of tree aggregations in forest ecology and management

Two recent studies using tree aggregations to analyze forest age-structure stability and past forest structure are flawed. A better understanding of aggregation dynamics is needed before aggregation analysis is used in forest management.     

南岳森林群落生物多样性研究(Ⅰ)广济寺森林群落学特征

根据我们对南岳广济寺森林群落的实地考察及其调查资料统计分析结果,发现该群落是一种尚未报道的新类型,即水丝梨+甜槠-尾叶山茶+花竹-蔓赤 车群丛(Association of Sycopsis sinensis+Castnopsis eyeri-Camellia caudata+Phyllostachys nidularia-Pellionia scabra)。该群落内有维管束植物69科116属149种;其属的区系是以热带性质成分为主,温带性质成分为辅,各占56.19％和43.81％;其种的区系成分以华夏、东亚、中国-日本和华东至华中等四种类型为主,同时本群落具有明显的华东至华中过渡交迭性质。在群落中木本植物和草本植物各占71.14％和28.86％,草本植物中的多年生和一年生类型各占22.82％和6.04％。本群落可以明显划分为乔、灌、草三个层次,每个层次又可以进一步划分为三个亚层。这一群落是中亚热带东部典型常绿阔叶林北部植被地理亚带中的常绿阔叶林,在演替过程中,群落仍将保持以水丝梨为优势种的常绿阔叶林,但其亚优势种——甜槠将可能会被多脉青冈、中华石楠、长叶石栎取代。     

Visual Aesthetic Quality of Northern Ontario's Forested Shorelines

Only a few empirical studies on forest aesthetics have adopted a water-based perspective for observers and have investigated the perceived visual quality of forested shorelines. In forested environments with many lakes, such as the boreal forest in the Canadian Shield, individuals have greater exposure to forests from water-based rather than in-stand vantage points. This study employed the psychophysical research direction to explore the relationships between scenic beauty and biophysical characteristics of the forested shorelines in the boreal forests. Two model forms were tested. One model related the variation of shoreline forest aesthetic evaluations of near-vista views (140 m offshore) to a set of forest mensuration data. Tree size, tree mortality, conifer shrubs, tree density, amount of hardwood, and slope explained 60.2% of the variance in scenic beauty between the study sites. A second model was calibrated to test the relationship between an already existing ecosystem vegetation classification system and the aesthetic evaluations of the same forested shorelines. When the ecosystem classification was simplified to eight groups, the model explained 48.5% of variance. These models suggest that the psychophysical approach to studying aesthetics can be applied successfully to near-vista evaluations of scenic beauty. The finding that a forest ecosystem classification system is highly related to scenic beauty suggests that, at least in the boreal forest, managers can reasonably estimate the scenic beauty of forested shoreline environments from an ecosystem classification, with little need for intensive data on these sites.     

激波与森林作用的实验研究

利用激波与森林的作用,有可能成为森林灭火中的一项新技术,本文报告了激波与林带作用的实验模拟方法,实验技术与装备,测试和显示手段等基本技术环节。激波在林地,林带中的传播和衰减,以及其它物理现象由纹影方法作了显示。激波诱导的压力场也作了测量。研究表明,以激波管为基础的模拟技术是成功的,实验结果对于进一步认识激波与林冠火阵面的相互作用有很好的先导意义。     

变坡度情况下森林地表上坡火行为若干特征的实验研究

应用自行研制的“多坡段固相材料火蔓延实验台”，模拟森林地表火的蔓延过程，对变坡度情况下森林地表上坡火行为规律进行了实验研究。研究发现，上坡火火焰随坡度的变化有三种火焰类型，即小坡度的缓慢燃烧，随坡度增加的火焰的抖动以及大坡度时的贴壁剧烈燃烧。     

兴文石林地质地貌景观的脆弱化趋势研究

兴文石林是喀斯特岩溶地质风景名胜区兴文石海的中心景区,喀斯特岩溶山地的生态环境具有一定脆弱特性,随着旅游业的不断发展,景区加大了开发力度,可能导致景区脆弱性的加剧,为了保证在旅游开发中能对景区重要的地质资源进行更好地保护,采用生态脆弱区评级指标及权重值评分法对兴文石林的10个主景点进行了研究,分析得出,兴文石林存在轻生态脆弱性、中生态脆弱性和强生态脆弱性三种梯度趋向,其中,脆弱性最强区域面积达到2平方公里的面积,这些区域分布在景区的边缘地带,因此,要实现旅游资源的可持续利用,必须对强生态脆弱性区域实行禁游和实行退耕还林等措施,以防止脆弱区域的扩大和脆弱性加剧.     

Assessing audit impact and thoroughness of VCS forest carbon offset projects

Voluntary markets transacted over $66 million USD of forest carbon offsets in 2016, according to Forest Trends, and over 99% of those offset projects were audited to a standard, primarily the Verified Carbon Standard (VCS). We provide a table characterizing all 70 validated and verified forest carbon projects employing the VCS version 3.0 currently-in-use (December 2011–July 2017). We also examine two separate aspects of the audit process––impact and thoroughness––to assess the effectiveness of the costly audit process, which can consume up to one-third of offset revenue. Audit impact we measure in terms of reduction in the number of offsets from ex ante estimated to ex post approved. Audit thoroughness we measure both directly in terms of the number of auditor hours worked per project and also indirectly in terms of the total number of Corrective Action Requests (CARs)/Non-Conformity Reports (NCRs) auditors prescribe. In terms of impact, we find that Afforestation/Reforestation/Restoration (A/R/R) and Improved Forest Management (IFM) projects, though only constituting 5% of total verified offsets, demonstrate significant (p < = 0.05) reductions from ex ante estimated to ex post approved offsets, likely because auditors can easily scrutinize carbon stocks/emission factors for the commercial tree species involved in these project types. In terms of thoroughness, we find that higher ex ante estimates correlate with more total auditor hours worked and total CARs/NCRs prescribed for three of four project activity types, likely because auditors perceive larger ex ante projects as higher risk. We conclude with recommendations for the VCS to empower auditors to scrutinize carbon stocks/emissions factors from avoided deforestation projects, and also to continue to flag high ex ante projects as higher risk.     

基于Logistic回归的林缘计划烧除气象条件判别分析

森林火灾是一种破坏性极强的灾害,它与农事活动以及气象条件密切相关,加强其预防与控制具有十分重要的作用和意义。根据2014年~2015年闽东屏南县进行的60次林缘计划烧除试验观测的主要气象要素数据(天晴日数、温度、湿度、风速),建立基于Logistic二元回归的林缘烧除气象条件判别模型进行检验和分析。结果表明,模型判别计划烧除成功与否的预报准确率高(91.7%),主要气象要素对林缘计划烧除成功与否发挥重要作用,其中连续晴天日数为最大影响因子,其次为风速。模型通过检验和验证结果显著,具有预报服务应用价值。     

Mitigation and adaptation synergy in forest sector

Mitigation and adaptation are the two main strategies to address climate change. Mitigation and adaptation have been considered separately in the global negotiations as well as literature. There is a realization on the need to explore and promote synergy between mitigation and adaptation while addressing climate change. In this paper, an attempt is made to explore the synergy between mitigation and adaptation by considering forest sector, which on the one hand is projected to be adversely impacted under the projected climate change scenarios and on the other provide opportunities to mitigate climate change. Thus, the potential and need for incorporating adaptation strategies and practices in mitigation projects is presented with a few examples. Firstly, there is a need to ensure that mitigation programs or projects do not increase the vulnerability of forest ecosystems and plantations. Secondly, several adaptation practices could be incorporated into mitigation projects to reduce vulnerability. Further, many of the mitigation projects indeed reduce vulnerability and promote adaptation, for example; forest and biodiversity conservation, protected area management and sustainable forestry. Also, many adaptation options such as urban forestry, soil and water conservation and drought resistant varieties also contribute to mitigation of climate change. Thus, there is need for research and field demonstration of synergy between mitigation and adaptation, so that the cost of addressing climate change impacts can be reduced and co-benefits increased.