Forest floor vegetation plays an important role in photosynthetic production of boreal forests

We estimated gross photosynthetic production (GPP) of the forest floor vegetation in a 40-year-old Scots pine stand in southern Finland with three different methods: measurements of CO₂ exchange of single leaves of field and ground layer species, measurement campaigns of forest floor net CO₂ efflux at different irradiances with a manually operated soil chamber, and continuous measurements of forest floor net CO₂ efflux with an automatic transparent chamber system. We upscaled the measured light response curves from the manual soil chambers using the biomass distribution of the forest floor species, a modelled seasonal pattern of photosynthetic capacity and a model of light extinction down the canopy. Leaf gas exchange measurements as well as measurements of net CO₂ efflux with the manual chamber indicated saturation of photosynthesis at relatively low (50–400 μmol m⁻² s⁻¹) light levels. Leaf and patch level measurements gave similar rates of photosynthetic CO₂ fixation per unit leaf biomass suggesting that reduction in photosynthetic production due to within-patch shading was small. Upscaling of photosynthetic production to the stand level and continuous measurements with the automatic soil chambers indicated that momentary photosynthetic production by the forest floor vegetation in the summer was typically about 2 μmol m⁻² (ground) s⁻¹. Cumulative upscaled GPP over the period of no snow (from 20 April to 20 November) in year 2003 was 131 g C m⁻². Continuous measurements with the automatic soil chamber system were in line with the upscaling, the cumulative GPP being 83 g C m⁻² and the seasonal pattern of photosynthetic rate similar to that of the upscaled photosynthesis.     

Forest vegetation of Xishuangbanna, south China

1 Introduction The tropical area of southern China is climatically and biogeographically located at the northern edge of tropical Asia, including southeastern Xizang (Tibet, lower valleys of the southern Himalayas), southern Yunnan, southwestern Guangxi, southern Taiwan and Hainan Island. The largest tropical area still covered by forests is in southern Yunnan. Tropical forests of southern Yunnan were little known until the late 1950s because of poor access except for some brief descrip-…     

Influence of edge and topography on the vegetation in an Atlantic Forest remnant in northeastern Brazil

Like edge effects, variations in topography can influence the physiognomy and structural patterns of the vegetation due to the high dynamics encountered in inclined areas. We evaluated the effect of edges on the structure and physiognomy of the arboreal and woody understory communities in patches of an Atlantic Forest remnant in two distinct topographic positions. Four study situations were laid out (slope edge, top edge, slope interior, and top interior), with ten 10 × 10 m plots each to sample the arboreal components (circumference at breast height ≥15 cm), and ten 5 × 5 m plots (in the corner of each arboreal component plot) to sample the woody understory (circumference at ground level ≥3 cm and with circumference at breast height <15 cm). We investigated physiognomic and structural variables of edge and interior environments in similar topographic positions on both slope and top (level) areas of the same remnant forest. Physiognomic and structural differences between edge and interior vegetation were noted, and these were found to be still more evident when different topographic positions were considered. Physiognomic and structural variations between the edge and interior vegetation were more notable on slopes than on hill tops, indicating greater dynamics in areas with greater topographic inclinations.     

天门山国家森林公园植被调查

通过实地调查和统计分析,将天门山国家森林公园植被划分为3个植被型组,7个植被型,12个群系,其中以常绿阔叶林、常绿-落叶阔叶混交林、落叶阔叶林3个植被型为主。本文较为详细地分析阐述了各个群系,总结概括了天门山植被特征。     

森林经营体系概论

林业两大体系建设和两个根本性转变要求构建科学的森林经营体系。采用以组织森林经营类型为核心的龄级法森林经营体系，优化森林经营决策，能有效地解决森林经营中存在的问题，合理配置林地资源，发挥森林资源三大效益。     

ISO9001:2000质量管理体系认证简介

简述了ISO9000族的发展、认证过程、八项质量管理原则及其推行的作用。     

Forest policy and sustainable forest management in Bangladesh: an analysis from national and international perspectives

This paper includes a review of international sustainable forestry development followed by an analysis of forest policies in Bangladesh. There have been four different government forest policies in Bangladesh since 1894. The first two forest policies (1894 and 1955) were exploitative in nature. Most of the regulatory documents were developed during the first two policy periods. The third forest policy instituted in 1979 by the sovereign Bangladesh government had contradictory elements and mutually inconsistent policy statements. It addressed for the first time forestry extension through mass motivation campaign. Current forest policy formulated in 1994 has been considered to be the most elaborate policy in the history of the country. Under this policy, participatory social forestry has been institutionalized in Bangladesh. The analysis shows that, although it is possible to attain the stated policy targets, progress is slow and is blocked on several fronts. A number of identified technical, managerial and logistical problems are hindering policy and program implementation. In addition, corruption contributes to the observed problems. The real strength of Bangladesh forestry is locally based, participatory forestry, co-management of protected areas and highly motivated people who increasingly recognize the need for a healthy forest ecosystem that will provide future economic stability. Because it is the rich homestead forests of Bangladesh that generate the majority of commercial forestry products, it is important that education continues at the grass-roots level. In addition, educated forestry and environment professionals have been identified as the future driving forces towards better, and sustainable, forest management. Results of this study make it clear that Bangladesh and other developing countries are not presently in a position to accept and adopt internationally derived forest policies due to inadequate institutional support, political instability and poor governance. Therefore, along with development of criteria and indicators of sustainable forest management and forest certification, international policy scientists must consider institutional development, professional skill development, identification and adoption of indigenous technology and long-term financial support in developing countries. Without these, all international processes, policies and directives will be of little value and produce few substantive results.     

天保工程公益造林后期管理

自2000年国家启动天然林资源保护工程以来，镇坪县积极争取生态公益林人工造林和封山育林工程项目，先后完成人工造林29003．6亩，封山育林25000亩，有效改善了生态环境，调整了林分结构，提高了林分质量。但造林质量、树种、林种的选择和后期管理等方面仍存在一些值得研究和探讨的问题。     

森林资源管理与监督

面对天保工程的新形势，林业工作者必须认真抓好森林资源管理与监督工作，采取行政的、法律的综合措施，切实抓好森林资源的各项管理和监督工作。只有这样才能确保“天保”工程顺利有序地进行。本文就做好森林资源管理与监督工作谈几点认识。１增强三种意识，是做好森林资源管理与监督工作的基础１．１资源意识。根据１９９８年第５次清查的结果，我国有１．５亿hm２森林面积，有１２４亿m３的森林蓄积。从总量上来说，我国的森林面积占世界第５位，森林蓄积占世界第６位。但是我国人均占有的森林面积只是世界平均水平的五分之一，人均占有…     

Forest ecosystem recovery in the southeast US: soil ecology as an essential component of ecosystem management

The forestry industry in the southeastern United States relies upon soils that are highly eroded and depleted of their original organic matter and nutrient content. Pro-active land management can ensure continued and possibly increased production and revenue through the management and recovery of the soil resource. With an emphasis on loblolly pine (Pinus taeda L.) forests, this review integrates land-use history, pine ecology, silviculture, soil ecological research and the implications for forest management into a single discussion. Promoting soil recovery involves knowledge of ecosystem history and disturbance as well as nutrient cycling mechanisms, pools, fluxes and soil forming factors. Research on the rhizosphere is an area that is needed. Recovery of regional soils may confer benefits of drought and disease resistance. The goal of sustainable forestry is compatible with soil recovery; however, the technology and practices of modern forestry deserve thorough evaluation. Emphasis on the continued production of commodities, the agricultural model, is much different from managing for the functioning of healthy forest ecosystems. Many of the practices and outcomes of intensive forest management, including short rotations, harrowing, subsoiling, and burning or removal of logging slash, seem to be at odds with the goal of soil recovery. Best management practices that foster soil recovery include less intensive stand utilization and reduced soil disturbance. Stem-only harvest and longer rotations permit a recovery of soil biodiversity and an accrual of detritus and soil organic matter. Windrowing and similar techniques have dramatic and lasting effects on soil development. No-tillage agriculture as a model for pine plantations is discussed.     

长沙县大山冲森林公园植被调查

大山冲森林公园森林植被主要由5个植被型组、9个植被型、27个群系组成,以樟科、山矾科、冬青科、壳斗科、漆树科、蔷薇科、山茶科等科为该地植被的优势科。植被类型多样,次生植物群落结构合理,能够正向演替,群落外貌季节性变化显著,针阔叶林交替变化,形成丰富多彩的季相特征。     

浅谈林下人参种植

人参为名贵中草药,高档天然补品。文章结合生产实践针对其种植选地、品种选择、种植及管理、起参、种子采集及主要经济技术指标等几方面总结了林下人参种植技术。     

森林经营与森林植物多样性

不同的森林经营方式和程度对森林生态系统造成的干扰程度不同,都会改变森林生态系统的多样性.依据中度干扰学说和林隙动态理论,采取合理的经营方式,控制干扰强度,是进行森林经营,维持森林多样性,实现森林可持续利用的一种有效方法.     

南方集体林区森林资源可持续经营的探讨

结合我国南方集体林区的林业生产情况，指出南方集体林区的森林资源管理没有摆脱“工业化林业”的阴影。在计划经济向社会主义市场经济体制转型时期，南方集体林区森林资源管理的目标、对象、森林经营的主体以及外部社会经济环境都发生了根本变化。因此南方集体林区的森林管理必须面对现实，适应社会经济的快速变化，在可持续发展的理论框架下，拓宽知识领域，将社会学、政策学、经济学融入森林资源管理，采取综合集成的方法和森林生态系统经营的途径，利用3S技术建立森林资源和环境评价、监测和动态管理体系。     

游憩践踏对张家界国家森林公园植被的影响研究

对张家界国家森林公园内植被的点状、线状和面状游憩践踏干扰进行了分析.结果表明:游憩践踏对植被覆盖度减少率、植相变异度、高度降低率、植物群落冲击指数有显著影响;不同践踏方式干扰对森林公园的植被影响有所不同.     

Effects of management regimes on carbon sequestration under the Natural Forest Protection Program in northeast China

Carbon sinks constitute an important element within the complex phenomenon of global climate change,and forest ecosystems are important global carbon sinks.The Natural Forest Protection Program(NFPP) is an ecological program in China that was established after catastrophic flooding in the country in 1998.The goals of the NFPP are to curb the deterioration of the ecological environment,strengthen the protection and restoration of habitat to increase biodiversity,and rehabilitate natural forests to support sustainable development in forest regions.This study looked at changes in carbon sequestration in a forested area of northeast China after the inception of the NFPP.The program divides China's natural forests into three classes—commercial and two types of noneconomic forests—that are subject to management regimes prescribing varying levels of timber harvest,afforestation,and reforestation.During the 18-year period from 1998 to 2015,the total amount of carbon sequestration increased at an average annual rate of 0.04 MT C.This trend reflects a transformation of forest management practices after implementation of the NFPP that resulted in prohibited and/or restricted logging and tighter regulation of allowable harvest levels for specific areas.In documenting this trend,guidelines for more effective implementation of forestry programs such as the NFPP in other countries in the future are also suggested.     

浅谈工程建设如何管理

本文作者详细论述了工程管理程序及应把握好几个重要环节。     

白石砬子山南北坡森林植被垂直分布的研究

文章对白石砬子山南北坡森林植被垂直分布按20m垂直海拔高度分段进行了植物种类、分布、多度的详细调查和分析。首次发现了兰科植物双花红门兰(Orchis cyclochila)的分布，填补了辽宁无此植物的空白。同时认为其植被分布有着特殊性，因此用温度随纬度、海拔递减规律估计各种植被分布误差较大。     

Regeneration behavior of competing plants after clear cutting: implications for vegetation management

Regeneration characteristics and population dynamics of four major competing plants, trembling aspen (Populus tremuloides Michx.), pin cherry (Prunus pensylvanica L.f.), green alder (Alnus viridis spp. crispa (Aiton) Turril) and beaked hazel (Corylus cornuta Marsh.) were studied from a seven-year-old clearcut in northwestern Ontario, Canada. The site was planted with jack pine two years after clearcutting. Regeneration strategies and population dynamics of these plants were studied by determining their crown diameter, stem density, stem height, stem age, depth of sprouting center, inter-sprout distance, oven-dry weight of shoots, roots plus rhizomes by nondestructive and destructive sampling. Stem density of trembling aspen and pin cherry in 1992 was 4580 and 3600 stems per ha respectively. Much higher stem density was obtained in green alder and beaked hazel during the same time, 27580 and 14600 stems per ha respectively. Substantial reduction in stem density was recorded in trembling aspen (45%) and pin cherry (69%) over two years, 1992–1994. However, reduction in stem density of green alder and beaked hazel for that period was very little (6 and 2%, respectively). Comparison of species' clonal characteristics of above- and below-ground components indicates that trembling aspen and pin cherry possess similar vegetative regeneration strategies that differ from those of green alder and beaked hazel. Ordination of the results of canonical variate analysis of the eight vegetative parameters of the four species arranged the species into two significantly different groups. Based on species regeneration strategies, two potential competition strategies were identified: a vertical competition strategy (VCS) and a horizontal competition strategy (HCS). We argue that the degree and duration of competition can be predicted from the density and ratio of VCS and HCS plants on a site once sufficient empirical data on the species' competitive abilities are gathered. We suggest that future studies should relate the regeneration strategies, population dynamics and competitive abilities of competing plants to competition tolerance of crop trees. This will fine tune our prediction about species interaction based on the present model and better justify the need for vegetation control intervention.