森林不同组分对降水的生态效应研究进展

森林是一个复杂的生态系统, 森林水文学是近年来研究的热点.大气降水作为森林生态系统养分来源之一, 是目前研究森林生态系统养分循环不可或缺的因子.典型的森林生态系统一般通过乔木层、灌草层、凋落物层和土壤层等组分对降水进行分配.文中系统阐述了国内外研究者关于森林生态系统各组分对降水生态效应的研究进展, 同时对森林降水中营养物质的输入和输出研究作了简述, 指出目前相关研究中存在的问题和今后努力的方向, 旨在为今后的研究提供参考.     

森林作业对林地土壤呼吸的影响

介绍了森林生态系统土壤呼吸的研究意义,森林生态系统土壤呼吸的影响因素,人为扰动对森林土壤呼吸影响的研究进展。提出了森林作业对土壤呼吸的作用机理和人为扰动对森林土壤呼吸各组分的微观影响,同时也提出土壤呼吸对森林生态系统的反馈作用是人为扰动对森林生态系统土壤影响研究中尚未解决的问题。     

全球气候变化及森林生态系统的适应性管理

人类活动所引起的温室效应及由此造成的全球气候变化对全球生态环境的影响正越来越引起人们的关注。森林作为全球陆地生态系统的一个重要组分, 对全球气候变化的响应较为敏感。文中系统总结了全球气候变化对物种和森林类型分布、森林生态系统结构和物种组成、森林生产力、森林土壤碳氮循环和森林灾害等几个方面的影响, 以及森林生态系统管理面临的挑战, 在此基础上提出了适应未来气候变化的森林生态系统管理策略。     

森林植被对土壤团聚体和微生物特性的影响研究进展

森林作为陆地生态系统的核心主体,具有维持生态系统平衡、保持水土、涵养水源等重要生态功能 。植被类型是 影响土壤团聚体形成和微生物特性的重要因子,研究森林植被类型对提高陆地生态系统生产力、丰富生物多样性及缓解全 球变暖等方面具有重要意义 。森林植被和土壤微生物及土壤团聚体的相互影响及交互作用,均对森林生态系统产生了 重 要影响 。本研究重点阐述了森林植被对土壤团聚体形成及稳定性、微生物生物量、微生物群落结构及功能等方面研究进 展,并提出未来森林生态系统的土壤团聚体与微生物方面的研究重点,以期为森林生态系统的植被恢复和可持续健康发展 研究提供理论依据。     

我国森林生态学研究的现状及其思考

森林生态学是研究森林及其与环境间相互关系的科学,森林生态系统作为陆地生态系统中一个重要类型和组成部分,对自然环境和人类的作用是明显的,在实现可持续发展中具有不可替代的作用。由于森林生态系统的复杂性和研究手段的相对滞后,目前森林生态学研究虽然取得很大的进展并成功应用于林业实践,但也存在一些问题。本文简要回顾和评述了我国森林生态学的发展和研究现状,着重指出目前研究中存在的不足,并结合现今森林生态学的发展趋势以及我们相关研究基础对森林生态系统的结构和功能研究、森林生态系统管理、森林流域生态学研究、森林生态系统健康等进行了讨论。参21。     

森林土壤呼吸对降雨脉冲的响应研究进展

森林生态系统的土壤碳储量是陆地生态系统碳库的重要组成部分。土壤呼吸则是土壤碳库参与陆地碳循环的主要方式,其受到诸多生物和非生物因子的综合调控。偶发性降雨会引起森林土壤湿度的瞬间增加,进而导致土壤呼吸速率的快速提高。文中介绍了森林土壤呼吸及其组分,综述了降雨脉冲效应的特征和诱导机制（包括物理替代机制、微生物代谢机制、土壤养分限制机制及光化学调控机制等）,分析了当前降雨脉冲研究存在的不足并展望了未来的研究重点,认为森林生态系统是未来开展降雨脉冲效应研究的重要方向,探究森林土壤呼吸不同组分对降雨脉冲的响应差异与机制也是潜在的重要研究方向。     

森林生态系统碳储量估测方法及其研究进展

森林生态系统作为陆地生态系统最大的碳库, 其碳交换对全球碳平衡有着重要影响, 研究其碳储量具有重要的科研和社会意义。文中阐述了森林生态系统碳储量研究进展及估测方法, 并展望了未来森林生态系统碳研究的主要方面。     

大型真菌多样性及在森林生态系统中的作用

从物种和生态环境差异两个方面来阐述了大型真菌的多样性,并且主要介绍了大型真菌的两个主要类群木腐菌和菌根菌以及各自在生态系统中的作用,在森林生态系统中,木材腐朽菌能将木材中的木质素、纤维素和半纤维素降解为植物可以利用的营养物质,从而完成系统中的物质循环,并且在木材腐朽分解的过程中,木腐菌的出现和演替有一定的规律性,不同时期都有其优势种存在,并对木材腐朽的进程起决定性作用。菌根真菌作为生态系统组分,它对物质循环,种间关系和群落的影响以及在生态系统变化过程中都起着非常重要的作用,是生态系统的重要组分。     

森林生态系统的矿质营养循环——矿物质循环的文献综述

矿物质营养循环是森林维持生产力的重要过程,矿物质和碳素之间具有微妙的平衡和依存关系,矿物质的吸收调节着森林生物量的增长,而碳素同化作用使矿物质被结合在有效物质中。矿物质循环是森林生态系统物质循环的基本的、重要的方面。从事森林生态系统矿物质循环的研究具有深刻的理论和生产实际意义。自1930年 Albert 的研究成果发表以来,森林生态系统矿物质循环的研究,已成为日益活跃的研究内容。苏联、美国、西德、日本、比利时等国在这方面都有不少研究成     

以昆虫为指示物种监测和评价森林生态系统健康初探

森林生态系统健康是保证生态系统服务功能的前提, 森林生态系统健康评价方法及指标体系已成为森林生态系统健康研究的核心内容。昆虫是森林生物多样性的重要组成部分, 在森林生态系统主体群落中, 昆虫与植物密切关联。森林害虫胁迫及昆虫多样性变动, 对于评估森林生态系统健康状况具有重要价值。研究显示, 昆虫多样性可应用于对森林生态系统健康的快速评估。     

Epiphyte diversity and biomass loads of canopy emergent trees in Chilean temperate rain forests: A neglected functional component

We document for the first time the epiphytic composition and biomass of canopy emergent trees from temperate, old-growth coastal rainforests of Chile (42°30′S). Through tree-climbing techniques, we accessed the crown of two large (c. 1 m trunk diameter, 25–30 m tall) individuals of Eucryphia cordifolia (Cunoniaceae) and one large Aextoxicon punctatum (Aextoxicaceae) to sample all epiphytes from the base to the treetop. Epiphytes, with the exception of the hemi-epiphytic tree Raukaua laetevirens (Araliaceae), were removed, weighed and subsamples dried to estimate total dry mass. We recorded 22 species of vascular epiphytes, and 22 genera of cryptogams, with at least 30 species of bryophytes, liverworts and lichens. The dominant vascular epiphytes were Fascicularia bicolor (Bromeliaceae), Raukaua laetevirens, Sarmienta repens (Gesneriaceae), and filmy ferns (Hymenophyllaceae). Epiphyte loads per tree ranged between 134 and 144 kg dry mass, with 60–70% water. The hemi-epiphytic tree R. laetevirens added between 1 and 2.6 t of dry mass to each host tree. A main component of epiphyte biomass, making 70% of the weight, was detritus and roots, while leaves, stems, and fronds made up the remaining 30%. Emergent trees hold a high proportion of the regional diversity of epiphytes: 33% of all flowering epiphytes, and 50% of all filmy ferns described for Chilean temperate forests. Dry epiphyte biomass associated only with the emergent E. cordifolia trees in coastal forests was estimated in 10 t/ha. Epiphyte biomass may store up to 300 l of water in each emergent tree, and add 40–150% of photosynthetic biomass to the tree crowns. Based on this evidence, epiphytes may play key but generally neglected roles in ecosystem carbon uptake, water storage, and nutrient cycling. Moreover, emergent trees represent nuclei of biodiversity and ecosystem functions distributed throughout mature forests. Forest management should recognize large trees as significant management units for the preservation of biodiversity and ecological functions.     

Vascular epiphytes loss in exploited trees of the semi deciduous managed forest of Ndelele,East Cameroon

ABSTRACT

Forest Management Unit (FMU) is a growing phenomenon in Cameroon, impacting biodiversity negatively. This study was initiated to assess vascular epiphytes’ species loss on exploited trees to suggest conservation strategies. We hypothesized that: 1) epiphyte loss in this managed forest was significantly high and different with respect to phorophyte species; 2) epiphyte diversity loss has threatened status. Epiphyte survey was conducted on four most exploited trees in this study area. 63 exploited trees (Phorophytes) were surveyed. Shannon, Chao1 and Sorensen’s similarity indexes were used. Kruskal–wallis test was used to test the hypotheses. We recorded (70 epiphyte species, 33 genera and 12 families). Orchidaceae constituted highest epiphyte species with 43 species (61.4%). Epiphytes diversity was similar with respect to different phorophyte species (Sorensen?50%). Shannon’s index (3.36) showed a high epiphyte diversity loss. Kruskal–wallis showed no significant difference in epiphyte loss between phorophytes but a significant difference between zones, with canopies losing the highest epiphytes. With one epiphyte species’ status almost threatened and epiphyte diversity loss (significant); strict sustainable conservation methods like: epiphyte shade-houses and relocation are solicited. More data are needed from similar and different managed forest strata for epiphyte conservation policy enactment in Cameroon.     

Community of vascular epiphytes on some phorophytes in the Babadjou Subdivision (Western Cameroon): Case of Bamelo

The environmental degradation of the western region of Cameroon has intensified over time and has contributed to the perturbation of the original floristic uniformity of pioneer vegetation. Epiphytes, which are very sensitive plants, have refuge mostly on phorophyte, hence permitting the evaluation of the conservation state of natural ecosystems. The present study aims to assess a floristic inventory of vascular epiphytes in the locality of Bamelo. Sampling was carried out on 100 individuals, 20 individuals for each of the five phorophyte species based on their abundance in the locality. A total of 36 species divided into eight families and 19 genera were recorded. Monocotyledons were the most abundant with 58.33% of community and represented only by the Orchidaceae family; pteridophytes and dicotyledons represent 22.22 and 19.44%, respectively. Persea amercina and Cola anomala were the most diversified phorophytes (19 species); Dacryodes edulis was the least diversified (eight). The principal component analysis revealed affinities between the epiphytic flora of Dacryodes edulis and Persea americana; Croton macrostachyus and Spathodea campanulata. At a time where the degradation of biodiversity occurs at an alarming rate, the conservation of such species becomes problematic. In view of the present results, epiphytes found refuge on fruit trees in plantations.     

ITTO热带用材林的生物多样性保护与可持续利用

为把生物多样性保护纳入森林可持续经营, 发挥热带用材林在生物多样性保护中的特殊作用, 国际热带木材组织先后于1993年和2009年出版了关于生物多样性保护与利用的两个指南。文中以热带森林的主要利益相关者为线索, 通过比较两个指南的差别, 探讨了热带用材林生物多样性保护与可持续利用的研究进展。     

Response of vascular epiphyte diversity to different land-use intensities in a neotropical montane wet forest

Although vascular epiphytes contribute substantially to the biodiversity of tropical montane forests, it is unclear how their diversity and community composition is affected by forest alteration. We studied the response of vascular epiphyte assemblages to different intensities of land-use in a montane wet forest of northeastern Ecuador: (1) unmanaged mature forest; (2) mature forest with mid- and understorey opened for cattle grazing; and (3) isolated remnant trees in cattle pastures. The numbers of individuals and species of epiphytes per host tree did not differ significantly between land-use types, neither did total epiphyte species richness (n = 30 trees). However, total species richness of pteridophytes was significantly lower on isolated remnant trees compared to unmanaged forest, whereas several taxa rich in xerotolerant species (Bromeliaceae, Orchidaceae, Piperaceae) exhibited the opposite trend. An analysis of floristic composition using ordination (NMS) and randomisation techniques (MRPP) showed that epiphyte assemblages on isolated remnant trees were significantly distinct from unmanaged forest while managed forest was intermediate between those two vegetation types. Ordination analysis further indicated reduced floristic heterogeneity in disturbed habitats. These results suggest considerable, rapid species turnover since land-use change 6 years prior to study, with pteridophytes being replaced by more xerotolerant taxa. We attribute this floristic turnover primarily to changes in microclimate towards higher levels of light and desiccation stress associated with forest disturbance. Our results support the notion that community composition offers a more sensitive indicator of human disturbance than species richness.     

人工林在生物多样性保护中的作用

综述了近年来世界人工林的发展动态以及人工林在生物多样性保护方面的最新研究进展; 从人工林与乡土森林的比较中, 表明了多数情况下人工林支持的物种多样性并不少于乡土森林植被, 同时表明了人工林已经成为一些稀有、濒危物种的重要庇护所和替代生境, 在很大程度上支持了人工林并不是生物多样性〝沙漠〞的观点; 分析了影响人工林生物多样性的因素及保护人工林生物多样性的途径。     

Nature vs. nurture: managing relationships between forests,agroforestry and wild biodiversity

Many agroforestry systems are found in places that otherwise would be appropriate for natural forests, and often have replaced them. Humans have had a profound influence on forests virtually everywhere they both are found. Thus ‘natural’ defined as ‘without human influence’ is a hypothetical construct, though one that has assumed mythological value among many conservationists. Biodiversity is a forest value that does not carry a market price. It is the foundation, however, upon which productive systems depend. The relationship between agroforestry and the wild biodiversity contained in more natural forests is a complicated one, depending on the composition of the agroforestry system itself and the way it is managed. Complex forest gardens are more supportive of biodiversity than monocrop systems, shade coffee more than sun coffee, and systems using native plants tend to be more biologically diverse. Nonnative plants, especially potentially invasive alien species, threaten biodiversity and need to be avoided. The relationship between forests, agroforestry and wild biodiversity can be made most productive through applying adaptive management approaches that incorporate ongoing research and monitoring in order to feed information back into the management system. Maintaining diversity in approaches to management of agroforestry systems will provide humanity with the widest range of options for adapting to changing conditions. Clear government policy frameworks are needed that support alliances among the many interest groups involved in forest biodiversity.

     

国内外混交林研究进展

在应对气候变化与实现碳中和目标以及社会发展对森林生态系统要求更加多样化的时代背景下,混交林的重要性在世界各国已达成共识。通常认为,相对于纯林,混交林能够增加生物多样性、提高生产力、增加碳储量,具有更高的生态韧性（抵抗力与恢复力）。但混交林是否必然优于纯林,且混交林与生物多样性、生产力、碳汇、生态韧性以及混交效应的关系一直是国内外学者探讨与研究的问题。混交林绝不是简单的树种组合与排列,其结构与生态过程相对复杂。文中通过文献梳理,总结分析混交林与生物多样性、生产力、碳储量、生态韧性以及混交林经营管理5个方面的国内外研究成果,发现关于混交林与生态功能和生产力的关系研究结果多样,总的结论是,若要得到混交林的积极效应,不能单纯增加树种多样性,更重要的是要考虑树种特性、生态互补、林分结构以及立地和环境的影响。我国混交林研究主要是通过造林实验对比分析生长效果,选择较优混交造林技术。文中最后提出我国混交林研究发展建议,旨在促进对混交林的科学和全面认识。     

Adaptive risk management for certifiably sustainable forestry

The past decade has seen a global surge in forest management certification, with over 200 million hectares of the world's forest now certified as sustainably harvested. Because forests are some of the most species-rich environments on earth and more than 90% of the world's forests occur outside formal protected area systems, forest management certification will be one of the pervasive influences on global biodiversity for the foreseeable future. We find that current forest certification schemes are largely deficient because they fail to demand: (i) measurable management objectives for biodiversity, (ii) formal risk assessment of competing management options that integrate impacts on biodiversity, (iii) monitoring that directly addresses management performance requirements and a clear plan for how monitoring information will be used to make better management decisions, and (iv) ongoing research targeted toward practices that enhance biodiversity in managed landscapes. We argue that the credibility of certification schemes hinges on their ability to dictate scientifically defensible management systems for biodiversity conservation. We present a framework for adaptive risk management (ARM) of biodiversity that is both responsibly proactive and diligently reactive and recommend its incorporation in all certification schemes. We highlight the need for substantial government and agency investment in fostering ARM.     

城市森林与生物多样性保护

城市森林已成为现代化生态大都市建设的主体部分,而生物多样性是城市森林的天然“本底”。本文在分析城市森林主要功能和生物多样性在城市森林的作用基础上,提出了城市森林建设中多样性保护对策。