Floristic variation in ecotonal areas: Patterns,determinants and biogeographic origins of subtropical forests in South America

We present the first quantification of forest community composition and its relationship with environmental factors in South American subtropical Atlantic Forests. In this region, rain, seasonally dry and mixed forests form an ecotonal zone near the parallel of latitude 30°S. To investigate how well current knowledge on climatic effects and biogeographic distribution apply to subtropical ecotones, we tested the following expectations: (i) there is a floristic longitudinal gradient correlated to altitudinal and climatic gradients; (ii) climatic variables are more important than soil factors in shaping floristic composition; and (iii) there are three floristic regions in the southernmost limit of the Atlantic Forest biome that are expected to be distinct in composition, structure and biogeographical origin. We examined floristic composition and its relationship with environmental factors across 52 1‐ha permanent study areas in subtropical Brazil, containing in total 269 tree species ≥ 9.5 dbh (diameter at breast height). Climatic data, related to rainfall seasonality and temperature, as well as soil properties, were compiled from published sources or global data banks. Expectations one and two were confirmed, but expectation three was only partially met. Hierarchical cluster analysis divided the southernmost Atlantic Forests into four major groups (Rain, Seasonally Dry, Western Mixed and Eastern Mixed Forests). Overall, the tested environmental variables differed significantly among the four regions. Using indicator species analysis, we distinguished 46 indicator species, which had significant environmental preferences for one floristic region. These species can be used as indicators of environmental conditions or to determine to which floristic region a certain forest belongs. Biogeographic distributions differed between floristic groups, supporting the interpretation that Eastern Mixed Forests are relict forests of a temperate forest of Andean origin that occurred during colder palaeoclimates. Western Mixed Forests represent the main floristic ecotone between Seasonally dry and Eastern Mixed Forests.     

Identity and relationships of the Arboreal Caatinga among other floristic units of seasonally dry tropical forests (SDTFs) of north-eastern and Central Brazil

The tree species composition of seasonally dry tropical forests (SDTF) in north-eastern and central Brazil is analyzed to address the following hypotheses: (1) variations in species composition are related to both environment (climate and substrate) and spatial proximity; (2) SDTF floristic units may be recognized based on peculiar composition and environment; and (3) the Arboreal Caatinga, a deciduous forest occurring along the hinterland borders of the Caatinga Domain, is one of these units and its flora is more strongly related to the caatinga vegetation than to outlying forests. The study region is framed by the Brazilian coastline, 50th meridian west and 21st parallel south, including the Caatinga Domain and extensions into the Atlantic Forest and Cerrado Domains. Multivariate and geostatistic analyses were performed on a database containing 16,226 occurrence records of 1332 tree species in 187 georeferenced SDTF areas and respective environmental variables. Tree species composition varied significantly with both environmental variables and spatial proximity. Eight SDTF floristic units were recognized in the region, including the Arboreal Caatinga. In terms of species composition, its tree flora showed a stronger link with that of the Cerrado Dry Forest Enclaves. On the other hand, in terms of species frequency across sample areas, the links were stronger with two other units: Rock Outcrops Caatinga and Agreste and Brejo Dry Forests. There is a role for niche-based control of tree species composition across the SDTFs of the region determined primarily by the availability of ground water across time and secondarily by the amount of soil mineral nutrients. Spatial proximity also contributes significantly to the floristic cohesion of SDTF units suggesting a highly dispersal-limited tree flora. These units should be given the status of eco-regions to help driving the conservation policy regarding the protection of their biodiversity.     

Assessing the effects of forest management on epiphytic lichens in coppiced forests using different indicators

Abstract

Epiphytic lichens are one of the taxonomic groups most sensitive to forest management. Nevertheless, they have not yet been exhaustively included in the assessment of Sustainable Forest Management. This work aimed at evaluating the effects of forest management on epiphytic lichens in coppiced forests, exploring the spatial patterns of diversity and the composition of communities. Moreover, the goal was to compare the performance of four potential indicators for monitoring the effects of forest management on epiphytic lichens: total lichen diversity, species associated with intensive management, species associated with aged coppiced woodlands and Indicator Species Ratio (ISR). In humid Mediterranean Liguria, 50 sampling units were chosen in Castanea sativa and deciduous Quercus spp. forests subjected to different forest management practices: intensively managed coppice and aged coppice/high forest. The effect of forest management was evident in terms of species composition, since it was possible to find significantly associated species for each of the two management types. At each sampling site, the four indicators were calculated using Indicator Value Analysis and compared through correspondence analysis. The ISR was shown to be a more effective indicator, being independent of floristic composition and the occurrence of rare species.     

Conservation status of tropical dry forest remnants in Nicaragua: Do ecological indicators and social perception tally?

Intensive deforestation is reducing dry tropical forest areas worldwide and increasing its fragmentation. Forest remnants can be the basis for the future recovery of this forest type if appropriate management practices are applied. This requires a better knowledge of their conservation status and the assessment of their perceived value by land users. In this study we compare the structure, species richness and diversity of different types of tropical dry forest remnants in Nicaragua and we assess their conservation status based on a new index: Social simplified Importance Value Index (SsIVI). This index summarizes both ecological indicators and the perception by local stakeholders of the conservation status of the tree species present. Results show that gallery and hillslope forest remnants have higher species richness and diversity than isolated vestigial patches. In all remnants, species richness and diversity is higher in the tree layer than in the regeneration layer. No differences are observed in valorisation among different types of remnants either for the tree layer or for the regeneration layer. In the hillslope forests, where several degrees of disturbance are present, the valorisation decreases with increasing degradation. Results of species composition and forest structure indicate a strong degradation of dry tropical forest remnants in Nicaragua. However, the similar social valorisation of the three types of remnants suggests that they face similar threats but also similar opportunities to be preserved. A decrease in valorisation with increasing degradation warns about the potential loss of the most degraded areas, unless forest restoration is applied.     

A forest typology for monitoring sustainable forest management: The case of European Forest Types

Abstract

Sustainable forest management (SFM) is presently widely accepted as the overriding objective for forest policy and practice. Regional processes are in progress all over the world to develop and implement criteria and indicators of SFM. In continental Europe, a set of 35 Pan-European indicators has been endorsed under the Ministerial Conference on the Protection of Forests in Europe (MCPFE) to measure progress towards SFM in the 44 countries of the region. The formulation of seven indicators (forest area, growing stock, age structure/diameter distribution, deadwood, tree species composition, damaging agents, naturalness) requires national data to be reported by forest types. Within the vast European forest area the values taken by these indicators show a considerable range of variation, due to variable natural conditions and anthropogenic influences. Given this variability, it is very difficult to grasp the meaning of these indicators when taken out of their ecological background. The paper discusses the concepts behind, and the requirements of, a classification more soundly ecologically framed and suitable for MCPFE reporting than the three (un-informative) classes adopted so far: broadleaved forest, coniferous forest, mixed broadleaved and coniferous forest. We propose a European Forest Types scheme structured into a reasonably higher number of classes, that would improve the specificity of the indicators reported under the MCPFE process and its understanding.     

The effect of landscape fragmentation and forest continuity on forest floor species in two regions of Denmark

Abstract. Forest species composition was recorded in 82 forests in the Himmerland and Hornsherred regions in Denmark and analysed with respect to isolation (distance to other forests and areas of forest), forest continuity (older or younger than 200 yr), soil pH, tree species composition and seed dispersal groups. Continuity and isolation measures were correlated with forest species richness in Hornsherred. Myrmecochorous, autochorous, anemoballistic and endozoochorous species were markedly fewer in recent than in ancient forests. In Himmerland, patterns were much weaker and few significant correlations were found between forest species richness or different seed dispersal groups and continuity or isolation of the forests. Differences between the two regions may result from less intensive land use, a more humid climate and a smaller species pool with less species with short distance dispersal in Himmerland. Landscape fragmentation therefore appears to limit forest species’recolonization more in Hornsherred than in Himmerland.     

A phytogeographic analysis of cloud forests and other forest subtypes amidst the Atlantic forests in south and southeast Brazil

In a previous study near the summit of Mt. Cuscuzeiro (Ubatuba, SP) (820–1270 m), on the SE Brazilian coast, we found two floristically different forests, one above 1120 m, that appears to have a number of features typical of cloud forests, and another on the lower altitude slopes below. Taking these two forests as reference points, we addressed two questions: (1) What are their floristic relationships with other Atlantic forest subtypes in S-SE Brazil?; (2) Do the cloud forests in this region constitute a particular floristic-phytogeographic formation or are they a subset of their surrounding community? Species from 109 surveys (including Mount Cuscuzeiro) of 83 locations in S-SE Brazil were compiled into a binary (presence-absence) floristic matrix. Analyses of similarity among these samples using clustering (UPGMA, TWINSPAN) and ordination (DCA, PCO and CA) methods were performed. The surveys were divided into six main groups: (1) Cloud Forests; (2) “Salesópolis” group (3) Coastal Forests, subdivided between (a) Slope Forests and (b) Coastal Plain (“Restinga”) Forests and Mountaintop Forests (not included in the Cloud Forests group); (4) Araucaria Forests; (5) Inland Seasonal Forests (from below ca. 700 m); and (6) Inland Montane Forests (from above ca. 700 m). The preferential and indicator species of the Cloud Forest group produced by TWINSPAN are presented. The Mount Cuscuzeiro forests from above and from below 1120 m were clustered with the Cloud Forests and the coastal Slope Forests groups, respectively. We concluded that Cloud forests comprise a distinct phytogeographic formation in Brazilian S-SE region.     

湖北省栲类林群落学特征研究

通过设置样方,在全面调查湖北省内各栲类林的基础上,对湖北省栲类林的物种组成、区系成分、群落结构及类型,以及影响群落结构的环境因子进行研究。结果显示：（1）在所调查的湖北省栲类林中共记录维管植物88科210属376种,其中乔木层中常绿树种有73种、落叶树种有48种,构成了以常绿树种为主的典型常绿阔叶林;（2）从科的区系组成来看,热带成分多于温带成分;从属的区系组成来看,热带成分与温带成分大体相当;（3）湖北栲类林生物多样性有显著的经度和海拔格局,但受纬度影响不大。土壤因子中仅氮含量对物种多样性格局影响显著;（4）湖北省栲类林可分为5个群系,即：苦槠（Castanopsis sclerophylla（Lindl.）Schott）林、钩栲（Castanopsis tibetana Hance）林、栲（Castanopsis fargesii Franch）林、甜槠（Castanopsis eyrei（Champ.）Tutch.）林和罗浮栲（Castanopsis faberi Hance）林。在各环境因子中,海拔、经度、坡度和土壤磷含量对群落组成的影响最大,地理因子和土壤因子对栲类林群落组成影响的总解释率为68.94%;（5）在5个群系中大部分乔木及栲属植物的径级分布呈单峰形,种-多度分布表现为典型的具有少数常见种、多个偶见种的倒“J”形曲线。研究表明湖北省栲类林物种多样性高,生物多样性丰富,植物区系热带成分明显,主要包含5个群系,地理因子和土壤因子可以解释大部分的群落物种组成变异。该研究可为湖北省常绿阔叶林保护和管理提供理论依据和数据支持。     

Indicators of restoration success in riparian tropical forests using multiple reference ecosystems

Forest restoration by planting trees often accelerates succession, but the trajectories toward reference ecosystems have rarely been evaluated. Using a chronosequence (4–53 years) of 26 riparian forest undergoing restoration in the Brazilian Atlantic Forest, we modeled how the variables representing forest structure, tree species richness and composition, and the proportion of plant functional guilds change through time. We also estimated the time required for these variables to reach different types of reference ecosystems: old‐growth forest (OGF), degraded forest, and secondary forest. Among the attributes which follow a predictable trajectory over time are: the basal area, canopy cover, density and tree species richness, as well as proportions of shade tolerant and slow growing species or individuals. Most of the variation in density of pteridophythes, lianas, shrubs and phorophythes, proportion of animal‐dispersed individuals, rarefied richness and floristic similarity with reference ecosystems remain unexplained. Estimated time to reach the reference ecosystems is, in general, shorter for structural attributes than for species composition or proportion of functional guilds. The length of this time varies among the three types of reference ecosystems for most attributes. For instance, tree species richness and proportion of shade tolerant or slow growing individuals become similar to secondary forests in about 40 years, but is estimated to take 70 years or more to reach the OGF. Of all the variables considered, canopy cover, basal area, density, and richness of the understory—by their ecological relevance and predictability—are recommended as ecological indicators for monitoring tropical forest restoration success.     

Tree age,disturbance history,and carbon stocks and fluxes in subalpine Rocky Mountain forests

Forest carbon stocks and fluxes vary with forest age, and relationships with forest age are often used to estimate fluxes for regional or national carbon inventories. Two methods are commonly used to estimate forest age: observed tree age or time since a known disturbance. To clarify the relationships between tree age, time since disturbance and forest carbon storage and cycling, we examined stands of known disturbance history in three landscapes of the southern Rocky Mountains. Our objectives were to assess the similarity between carbon stocks and fluxes for these three landscapes that differed in climate and disturbance history, characterize the relationship between observed tree age and time since disturbance and quantify the predictive capability of tree age or time since disturbance on carbon stocks and fluxes. Carbon pools and fluxes were remarkably similar across the three landscapes, despite differences in elevation, climate, species composition, disturbance history, and forest age. Observed tree age was a poor predictor of time since disturbance. Maximum tree age overestimated time since disturbance for young forests and underestimated it for older forests. Carbon pools and fluxes were related to both tree age and disturbance history, but the relationships differed between these two predictors and were generally less variable for pools than for fluxes. Using tree age in a relationship developed with time since disturbance or vice versa increases errors in estimates of carbon stocks or fluxes. Little change in most carbon stocks and fluxes occurs after the first 100 years following stand‐replacing disturbance, simplifying landscape scale estimates. We conclude that subalpine forests in the Central Rocky Mountains can be treated as a single forest type for the purpose of assessment and modeling of carbon, and that the critical period for change in carbon is < 100 years.     

Tree diversity drives diversity of arthropod herbivores,but successional stage mediates detritivores

The high tree diversity of subtropical forests is linked to the biodiversity of other trophic levels. Disentangling the effects of tree species richness and composition, forest age, and stand structure on higher trophic levels in a forest landscape is important for understanding the factors that promote biodiversity and ecosystem functioning. Using a plot network spanning gradients of tree diversity and secondary succession in subtropical forest, we tested the effects of tree community characteristics (species richness and composition) and forest succession (stand age) on arthropod community characteristics (morphotype diversity, abundance and composition) of four arthropod functional groups. We posit that these gradients differentially affect the arthropod functional groups, which mediates the diversity, composition, and abundance of arthropods in subtropical forests. We found that herbivore richness was positively related to tree species richness. Furthermore, the composition of herbivore communities was associated with tree species composition. In contrast, detritivore richness and composition was associated with stand age instead of tree diversity. Predator and pollinator richness and abundance were not strongly related to either gradient, although positive trends with tree species richness were found for predators. The weaker effect of tree diversity on predators suggests a cascading diversity effect from trees to herbivores to predators. Our results suggest that arthropod diversity in a subtropical forest reflects the net outcome of complex interactions among variables associated with tree diversity and stand age. Despite this complexity, there are clear linkages between the overall richness and composition of tree and arthropod communities, in particular herbivores, demonstrating that these trophic levels directly impact each other.     

Effects of forest continuity and tree age on epiphytic lichen biota in coniferous forests in Estonia

Epiphytic lichen biota on Picea abies and Pinus sylvestris in Estonia was studied. Twenty-one spruce and 21 pine sample plots were located in old forests with long forest continuity, and 12 spruce and 12 pine sample plots in young first-generation forests (<100 years). Altogether 103 lichen species were recorded on the 330 sampled trees. Lichen species richness per plot was significantly higher in old forests in case of both tree species; 31 lichen species, including red-listed and protected species, were found only in old forests. Tree age had a positive effect on lichen species richness on tree stem in old and young spruce forests and in young pine forests. Tree age also had an effect on the presence of several species. Both tree age and forest continuity affected lichen species composition. Arthonia leucopellaea, Chrysothrix spp. and Lecanactis abietina were found in at least every third old spruce or pine forest and in no young forests, and can be regarded as good indicators of old coniferous forests with long continuity in Estonia.     

Stand height and cover type complement forest age structure as a biodiversity indicator in boreal and northern temperate forest management

Forest age structure is one of the main indicators of biodiversity in temperate and boreal forests worldwide. This indicator was mainly chosen for the conservation of a subset of rare or sensitive species related to the oldest age classes, not to capture variability across the entire biodiversity spectrum, but is often considered as such. In this study, we analysed alpha and beta diversity in temporary plots of western Quebec, Canada, to consider biodiversity indicators complementary to existing forest age structure targets. Our analysis revealed that considered individually, stand characteristics such as cover type and height are better predictors of changes in site-level contribution to tree beta diversity than age. We also show that plots belonging to different age classes can be similar in terms of tree alpha diversity. Height class was found to have a more significant impact on tree alpha diversity than expected: height was more important than age in coniferous forests, and in deciduous and mixedwood stands it frequently complemented age in explaining the observed diversity patterns. Our results suggest that forest age structure target levels should not be used as the sole indicator of ecosystem sustainability, and that some mature secondary stands can provide significant contributions to biodiversity. We propose that more efficient trade-offs between forest exploitation, ecosystem functioning and environmental conservation can be attained if: (i) forest age structure targets are complemented by cover type and stand height; or (ii) complementary biodiversity indicators of ecosystem sustainability are implemented.     

Understorey plant species richness and composition in metropolitan forest archipelagos: effects of forest size, adjacent land use and distance to the edge

Aim To address the relative role of adjacent land use, distance to forest edge, forest size and their interactions on understorey plant species richness and composition in perimetropolitan forests. Location The metropolitan area of Barcelona, north‐eastern Spain. Methods Twenty sampling sites were distributed in two forest size‐categories: small forest patches (8–90 ha) and large forest areas (> 18,000 ha). For each forest‐size category, five sites were placed adjacent to crops and five sites adjacent to urban areas. Vascular plant species were recorded and human frequentation was scored visually in 210 10 × 10 m plots placed at 10, 50 and 100 m from the forest edge, and additionally at 500 m in large forest areas. Plant species were grouped according to their ecology and rarity categories. A nonmetric multidimensional scaling (NMS) ordination was carried out to detect patterns of variation in species assemblage, and to explore the relationships between these patterns and the richness of the species groups and the studied factors. Factorial anovas were used to test the significance of the studied factors on the richness of species groups. Relationships between human frequentation and the studied variables were assessed through contingency tables. Results Forest‐size category was the main factor affecting synanthropic species (i.e. those thriving in man‐made or man‐disturbed habitats). Synanthropic species richness decreased with increasing distance from the forest edge and, when forests were adjacent to crops, it was higher in small forest patches than in large forest areas. Richness of rare forest species was lower in small forest patches than in large forest areas when forests were adjacent to urban areas. Richness of common forest species and of all forest species together were higher close to the forest edge than far from it when forests were adjacent to urban areas. Forests adjacent to urban areas were more likely to experience high human frequentation, particularly in those plots nearest to the forest edge. Main conclusions Forest‐size category and adjacent land use were the most important factors determining species richness and composition. The preservation of large forests adjacent to crops in peri‐urban areas is recommended, because they are less frequented by humans, are better buffered against the percolation of nonforest species and could favour the persistence of rare forest species.     

Winning and Losing Tree Species of Reassembly in Minnesota’s Mixed and Broadleaf Forests

We examined reassembly of winning and losing tree species, species traits including shade and fire tolerance, and associated disturbance filters and forest ecosystem types due to rapid forest change in the Great Lakes region since 1850. We identified winning and losing species by changes in composition, distribution, and site factors between historical and current surveys in Minnesota’s mixed and broadleaf forests. In the Laurentian Mixed Forest, shade-intolerant aspen replaced shade-intolerant tamarack as the most dominant tree species. Fire-tolerant white pine and jack pine decreased, whereas shade-tolerant ashes, maples, and white cedar increased. In the Eastern Broadleaf Forest, fire-tolerant white oaks and red oaks decreased, while shade-tolerant ashes, American basswood, and maples increased. Tamarack, pines, and oaks have become restricted to sites with either wetter or sandier and drier soils due to increases in aspen and shade-tolerant, fire-sensitive species on mesic sites. The proportion of shade-tolerant species increased in both regions, but selective harvest reduced the applicability of functional groups alone to specify winners and losers. Harvest and existing forestry practices supported aspen dominance in mixed forests, although without aspen forestry and with fire suppression, mixed forests will transition to a greater composition of shade-tolerant species, converging to forests similar to broadleaf forests. A functional group framework provided a perspective of winning and losing species and traits, selective filters, and forest ecosystems that can be generalized to other regions, regardless of species identity.     

Bole epiphytic lichens as potential indicators of environmental change in subtropical forest ecosystems in southwest China

Lichen epiphytes are applied as excellent environmental indicators worldwide. However, very little is known about epiphytic lichen communities and their response to forest dynamics in subtropical China. This paper proposes the applications of the cover, diversity, and functional traits of epiphytic lichens to assess environmental changes associated with succession in subtropical forests of southwest China. Bole lichens were sampled from 120 plots of eight representative forest types in the Ailao Mountains. Total cover, species richness, diversity and community structure of bole lichens differed significantly among forest types, and the highest cover and diversity occurred in the Populus bonatii secondary forest (PBSF). Sixty-one indicator species were associated with particular forest types and more than 50% occurred in the PBSF. Both cover and diversity of most lichen functional groups varied regularly during forest succession. Lichen pioneer species were not displaced by competitively superior species as succession proceeds and cyanolichens were more prevalent in secondary forests. The results also highlight the importance of habitat variables such as canopy openness, host diversity, forest age, tree size, the size of the largest tree, tree density, and basal area on the lichen community. Consequently, our findings support the notion that epiphytic lichens, in terms of cover, diversity, species composition and functional traits can be used as effective indicators for large-scale and long-term forest monitoring. More importantly, the narrowly lobed foliose group was the best candidate indicator of environmental conditions in this region. The combined application of lichen indicator species and functional groups seemed to be a more reliable and more powerful method for monitoring forest dynamics in subtropical montane ecosystems.     

石门国家森林公园典型杉木林植被结构分析

以石门国家森林公园典型南亚热带杉木(Cunninghamia lanceolata)林为对象,对林分内乔木层、灌木层、层间层、草本层的组成及多样性进行调查分析。结果表明,调查区内杉木林乔木层主要树种为杉木、木荷(Schima superba)、马尾松(Pinus massoniana)、罗浮柿(Diospyros morrisiana)、华润楠(Machilus chinensis)、鸭脚木(Schefflera octophylla)等,杉木占比39.7%～68.7%,其他阔叶树占比31.3%～60.3%;林下植物灌木有50种,层间层有21种,草本有19种,具有较高的植物多样性,林下植物总体Shannon-Wiener多样性指数为2.73。该研究为南亚热带杉木林尤其是石门国家森林公园杉木林保育及促进森林植被向更高级阶段演替提供重要依据。     

Structure and Composition of Historical Longleaf Pine Ecosystems in Mississippi,USA

Longleaf pine (Pinus palustris) historically was a widespread ecosystem composed of a simple tree canopy and grasslands ground layer. After widespread loss of this ecosystem due to logging and fire exclusion, little quantitative information exists about historical structure for restoration goals. We identified composition in De Soto National Forest and Pearl River County, Mississippi, USA, and density, basal area, and percent stocking in Pearl River County using General Land Office surveys and US Forest Service Forest Inventory and Analysis surveys. Historical longleaf ecosystems were about 85% pine, with lesser amounts of broadleaf evergreen and oak species. Densities were about 175 to 180 trees/ha, mean tree diameters were 45 cm, and stocking was around 60% to 65%, which suggested longleaf pines were closed woodlands. Current forests are 38% to 57% pine, primarily loblolly, while longleaf pine is 2% to 8% of composition. Indeed, current longleaf pine composition across the Coastal Plain averages 3% and does not reach 10% at smaller landscape scales. Fire-sensitive broadleaf species of water oak, sweetgum, yellow-poplar, and red maple increased from about 0.5% composition to 2% to 10% of composition. Forests became twice as dense, at about 280 trees/ha to 330 trees/ha, with mean tree diameters of 22 cm. These results characterize conversion from open old growth longleaf forests, resulting in part from human maintenance, to successional forests due to human disruption of the historical ecosystem. It is important to remember structure and composition of historical forests for restoration and recognize wholesale changes so that successional forests do not become the new social and cultural baseline.     

Dominant forest tree mycorrhizal type mediates understory plant invasions

Forest mycorrhizal type mediates nutrient dynamics, which in turn can influence forest community structure and processes. Using forest inventory data, we explored how dominant forest tree mycorrhizal type affects understory plant invasions with consideration of forest structure and soil properties. We found that arbuscular mycorrhizal (AM) dominant forests, which are characterised by thin forest floors and low soil C : N ratio, were invaded to a greater extent by non‐native invasive species than ectomycorrhizal (ECM) dominant forests. Understory native species cover and richness had no strong associations with AM tree dominance. We also found no difference in the mycorrhizal type composition of understory invaders between AM and ECM dominant forests. Our results indicate that dominant forest tree mycorrhizal type is closely linked with understory invasions. The increased invader abundance in AM dominant forests can further facilitate nutrient cycling, leading to the alteration of ecosystem structure and functions.     

Conservation gains through HCVF assessments in Bosnia-Herzegovina and Romania

This paper analyses the conservation gains through High Conservation Value Forest (HCVF) assessments in two South-East European countries (Bosnia-Herzegovina and Romania). These are based on the review of the Draft Forest Stewardship Council (FSC) National Standards and HCVF Manuals and the results of the certification process of seven forest management units in the two countries. The review indicates that the application of Principle 9 (High Conservation Value Forests) and Criterion 6.4 of the FSC in Bosnia-Herzegovina and Romania was influenced by the size and nature of tenure (i.e., public or non-public land), rather than geographic location per se. The study also revealed that the assessment of HCVF has, for the first time, raised the question of conservation of cultural, historical and religious values as well as the sustainable management of those forests relevant for the basic needs of communities. These are values not currently covered at the present by the national conservation legislation in either of these two countries. Findings of this study in both countries demonstrates that there are certain conservation gains as a result of the HCVF assessment, especially related to ecosystem services, prevention of soil erosion and conservation of threatened, endangered and endemic species.