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International audience; Forest dynamics are shaped by both abiotic and biotic factors. Trees associating with different types of mycorrhizal fungi differ in nutrient use and dominate in contrasting environments, but it remains unclear whether they exhibit differential growth responses to local abiotic and biotic gradients where they co-occur. We used 9-year tree census data in a 25-ha old-growth temperate forest in Northeast China to examine differences in tree growth response to soil nutrients and neighborhood crowding between tree species associating with arbuscular mycorrhizal (AM), ectomycorrhizal (EM), and dual-mycorrhizal (AEM) fungi. In addition, we tested the role of individual-level vs species-level leaf traits in capturing differences in tree growth response to soil nutrients and neighborhood crowding across mycorrhizal types. Across 25 species, soil nutrients decreased AM tree growth, while neighborhood crowding reduced both AM and EM tree growth, and neither soil nor neighbors impacted AEM tree growth. Across mycorrhizal types, individual-level traits were stronger predictors of tree growth than species-level traits. However, most traits poorly mediated tree growth response to soil nutrients and neighborhood crowding. Our findings indicate that mycorrhizal types strongly shape differences in tree growth response to local soil and crowding gradients, and suggest that including plant-mycorrhizae associations in future work offers great potential to improve our understanding of forest dynamics.

Overhunting is a leading contemporary driver of tropical forest wildlife loss. The absence or extremely low densities of large-bodied vertebrates disrupts plant-animal mutualisms and consequently degrades key ecosystem services. Understanding patterns of defaunation is therefore crucial given that most tropical forests worldwide are now “half-empty”. Here we investigate changes in vertebrate community composition and size structure along a gradient of marked anthropogenic hunting pressure in the Médio Juruá region of western Brazilian Amazonia. Using a novel camera trapping grid design deployed both in the understorey and the forest canopy, we estimated the aggregate biomass of several functional groups of terrestrial and arboreal species at 28 sites along the hunting gradient. Generalized linear models (GLMs) identified hunting pressure as the most important driver of aggregate biomass for game, terrestrial, and arboreal species, as well as nocturnal rodents, frugivores, and granivores. Local hunting pressure affected vertebrate community structure as shown by both GLM and ordination analyses. The size structure of vertebrate fauna changed in heavily hunted areas due to population declines in large-bodied species and apparent compensatory increases in nocturnal rodents. Our study shows markedly altered vertebrate community structure even in remote but heavily settled areas of continuous primary forest. Depletion of frugivore and granivore populations, and concomitant density-compensation by seed predators, likely affect forest regeneration in persistently overhunted tropical forests. These findings contribute to a better understanding of how cascading effects induced by historical defaunation operate, informing wildlife management policy in tropical peri-urban, rural and wilderness areas.

Microhabitat preference among primates, which provides them with the niche they need to survive, often conditions primate diversity, abundance, and coexistence. Vegetation alteration and recovery have built heterogeneous forest landscapes that may influence primates’ microhabitat preferences. We compared the diversity and size of trees/shrubs and the presence of lianas in 132 sites where we captured the rufous mouse lemur (Microcebus rufus), with that of 240 sites where we did not capture this species, to investigate the aspects of microhabitat structure they might prefer. We then examined how this structural preference varies across a heterogeneous landscape of forests with different disturbance levels. Overall, microhabitats used by M. rufus differed significantly from unused ones in densities of small size, understory, and midstory plants. Microcebus rufus frequented microhabitats with significantly denser small- and medium-size (diameter at breast height [DBH] 2.5–10 cm) trees/shrubs without lianas in the primary forest, and small-size plants (DBH 2.5–4.9 cm) with one liana in other forest types. Compared to the microhabitats they used in the primary forest, the microhabitats in other forest types had lower densities of trees/shrubs with lianas. Additionally, the secondary forests and forest fragments also had significantly lower DBH. Although this variation in microhabitat use may represent an opportunity for M. rufus to live in disturbed habitats, it may expose them to additional threats, affecting their long-term survival. These findings emphasize the need to examine potential changes in microhabitat use among primates living in anthropogenic landscapes, which could help optimize long-term conservation and management of threatened primate species in heterogeneous landscapes.

Forest structure and composition change are driven by complex interactions among local site factors, past site history, and region-specific socio-demographic factors. Previous studies suggest the structural, functional, taxonomic, and carbon storage potential of vegetation increases during succession. However, information on these attributes along an altitudinal gradient from the North East India is lacking for the old growth secondary forests. Therefore, the present study investigates (i) tree diversity and biomass carbon storage, and (ii) dominating and carbon important tree species, along an altitudinal gradient (30–700 m) in the tropical semi-evergreen forests of southern Assam. Random quadrats of 0.1 ha were laid over selected elevation gradient of secondary forest to evaluate tree diversity, density, basal area, and biomass carbon stock. Shannon–wiener index increases from 2.88 (at 30 m) to 3.33 (at 700 m) indicating an increase in species diversity with elevation. The stand density ranges from 920–1630 stems ha−1 and reciprocally related to the altitude. Palaquium polyanthum, Dysoxylum binectariferum, and Maniltoa polyandra were the most dominant species at 30 m, 300 m and 700 m, respectively. Biomass carbon stock decreases with the increase in altitude and ranges from 71.20 to 77.47 Mg ha−1. Palaquium ployanthum, Sterculia sp. and Syzygium cumini were the most carbon important species at 30 m, 300 m and 700 m, respectively. Present study suggests conservation and management of old-growth secondary forests have carbon storage and regional climate benefits. Management of such secondary forests can also enhance the resiliency of forest ecosystems to nature conservancy.

The present study compared patterns of diversity of the families Calliphoridae and Sarcophagidae (Diptera: Oestroidea) among areas of primary and secondary forest, and clearings in the Amazon biome. We evaluated the relationship between habitat specialist and generalist species, verifying their potential for use as bioindicator species. The study was conducted in 27 areas that comprise primary and secondary forests and clearings in the municipality of Juruti, Para, Brazil. We collected 4286 necrophagous flies in the three study environments. The hypothesis of dissimilarity in the diversity among environments was corroborated for the Sarcophagidae and partly upheld for the Calliphoridae. The sarcophagid species Oxysarcodexia carvalhoi (Lopes 1946), Oxysarcodexia fringidea (Curran and Walley 1934), Oxysarcodexia thornax (Walker 1849), and the calliphorids Chrysomya megacephala (Fabricius 1794) and Cochliomyia macellaria (Fabricius 1775) were all associated with clearing environments. No sarcophagid species were identified as indicators of primary forest. The calliphorids, Chloroprocta idioidea (Robineau-Desvoidy 1830) and Paralucilia adespota (Dear 1985) were identified as indicators of primary + secondary forest. The occurrence of indicator species and their levels of tolerance varied considerably between the two families. The calliphorids and sarcophagids both included species capable of representing differences in necrophagous fly’s diversity among clearing, primary and secondary forest environments, which increases the understanding of the ecology of the taxa and their potential use for biomonitoring, management, and habitat conservation. In general, sarcophagids had a strong relationship with clearings and secondary forest. Some species show intense scavenger behavior and preference for altered environments. This reinforces the importance of the relationship between species and landscapes. In calliphorids, only Chloroprocta idioidea was associated with primary and secondary forest. We also recorded calliphorid species that prefer clearings and secondary forest and are highly tolerant to variation from abiotic factors, with wide niche breadth due to preference for these landscape types. The niche breadth and the tolerance shown by the species are an indication of the potential success of these organisms in response to anthropic processes and changes in landscapes.

Global initiatives to reforest degraded areas have intensified in recent years, in an attempt to reverse the environmental impacts of habitat loss on species and ecosystem provided by them. However, the effectiveness of such reforestation initiatives in re-establishing biodiversity is still poorly understood. Here, we test how reforestation type and intensity applied to deforested areas affect the reestablishment of communities of cavity-nesting bees and wasps. We deployed experimental trap-nests along a reforestation gradient of increasing structural similarity to primary forest, after 18 years of reforestation. We found that reestablishment, in terms of abundance and richness of both bees and wasps, was greatest at an intermediate point along the reforestation gradient. However, these communities were highly dissimilar to primary forest, and recovery of intact insect community composition was only achieved when reforestation was more similar in structure to natural forests. This effect was more pronounced for bees than for wasps. Our findings suggest that along the reforestation gradient, services provided by wasps will be more easily recovered than those provided by bees. Our results have important implications for the challenges of restoring and maintaining species biodiversity as well as their associated ecosystem services.

The hermit beetle (Osmoderma barnabita) is an internationally protected specialist of tree hollows considered a relic of primeval forests. The backbone of its distribution in eastern Czechia, however, is a system of pollard willows in intensively farmed lowlands. Pollarding, a traditional agroforestry practice inducing formation of tree hollows, was partly abandoned in the area during the twentieth century. To assess the state of the system of pollard willows and to investigate parameters of pollards and their stands which affect the beetle’s presence. We inventoried pollard trees and beetle distribution across ca 2000 km2 of lowlands along the Dyje, Morava and Odra rivers and their tributaries in eastern Czechia and westernmost Slovakia. We found 10 441 pollard willows in 324 stands: most stands contained trees of large diameters and poor health; young trees were rare. Probability of O. barnabita presence increased with number of trees in stand, decreased with distance to the nearest occupied stand, and was further affected by the health state of trees. Our results show that high hollow density in pollards allows for the existence of specialized, dispersal limited forest organisms in virtually deforested landscapes. They suggest stands should contain at least 200–300 pollard willows to sustain the beetle population. Although the beetle is still widespread over the study area, the existing populations are isolated and subjected to extinction debt. Large-scale restoration of pollarding practice, planting and pollarding of numerous young trees, and increasing connectivity is vital to facilitate the survival of this hermit beetle population but also support other hollow associated organisms.

Extrapolative nonparametric estimators of species density are commonly used in community ecology. However, they are dependent on either (1) their use on non-dispersive taxa, or (2) the ability to separate tourists from residents in dispersive taxa. We undertook ten years of leaf litter sampling in an ancient woodland in the New Forest, Southern England. We identified all the beetles from those samples and assigned them a residency status (residents, stratum tourists, and habitat tourists). Extrapolations, using the Chao 2, first- and second-order jackknife, and bootstrap approaches, of all sampled beetles all showed large overestimates of species richness when compared with extrapolations based on just residents. We recommend that the estimators should be used with caution as estimates of actual species density for dispersive taxa unless the natural history of most species in a community is well known. This applies especially to tropical ecosystems where many species have not been described. This reinforces the need for more descriptive natural history.

Canopy soils on large trees are important for supporting the lives of many canopy plants, and thereby increasing regional biodiversity. However, because of the less accessibility to canopy soils, there is insufficient knowledge on how canopy soils produce available nitrogen (N) for canopy plants through the activity of canopy soil microbes. Canopy soils usually have different soil properties from ground soils, so we hypothesized that canopy soils would have unique microbial communities compared to ground soils, but still provide available N for canopy plants. Here, we compared soil N availability, including net N mineralization and nitrification rate, and microbial communities between canopy soils (organic soils) collected at various heights of a large Cercidiphyllum japonicum tree and ground soils (organic and mineral soils) in a cool-temperate old-growth forest of Japan. The canopy soils had significantly different N availability (mass-based higher but volume-based lower) and microbial communities from the ground mineral soils. Among organic soils, the height of the soil had an impact on the microbial communities but not on the N availability, which agreed with our hypothesis. Despite the decrease in fungal abundance in the higher soils, the increase in certain components of the cellulose-decomposing fungi and oligotrophic bacteria may contribute to the available N production. Also, the abundance of ammonia-oxidizers did not change with the height, which would be important for the nitrification rate. Our study implied canopy soils could provide N to canopy plants partly through the functional redundancy within different microbial communities and constant population of ammonia-oxidizers.

Tropical rainforest disturbance and conversion are critical drivers of biodiversity loss. A key knowledge gap is understanding the impacts of habitat modification on mechanisms of community assembly, which are predicted to respond differently between taxa and across spatial scales. We use a null model approach to detect trait assembly of species at local- and landscape-scales, and then subdivide communities with different habitat associations and foraging guilds to investigate whether the detection of assembly mechanisms varies between groups. We focus on two indicator taxa, dung beetles and birds, across a disturbance gradient of primary rainforest, selectively logged rainforest, and oil palm plantations in Borneo, Southeast Asia. Random community assembly was predominant for dung beetles across habitats, whereas trait convergence, indicative of environmental filtering, occurred across the disturbance gradient for birds. Assembly patterns at the two spatial scales were similar. Subdividing for habitat association and foraging guild revealed patterns hidden when focusing on the overall community. Dung beetle forest specialists and habitat generalists showed opposing assembly mechanisms in primary forest, community assembly of habitat generalists for both taxa differed with disturbance intensity, and insectivorous birds strongly influenced overall community assembly relative to other guilds. Our study reveals the sensitivity of community assembly mechanisms to anthropogenic disturbance via a shift in the relative contribution of stochastic and deterministic processes. This highlights the need for greater understanding of how habitat modification alters species interactions and the importance of incorporating species’ traits within assessments. Supplementary Information The online version contains supplementary material available at 10.1007/s00442-020-04829-z.

To assess phosphorus (P) status of forest soil under naturally restored vegetation, P fractions in the 10-cm soil layer were quantified at different successional stages on the clear-cut site of mixed broadleaved and Korean pine forest. Four communities of shrub, softwood broad-leaved forest, softwood and hardwood broad-leaved forest, and hardwood broad-leaved forest represented different successional stages. A soil sample from a primary broad-leaved and Korean pine stand was the control. A sequential P fractionation scheme extracted empirically defined pools of P and path analysis used to partition the direct and indirect contribution of soil P fractions to available P. The results show that available P increased significantly with long-term succession, while both sodium bicarbonate-extractable P (NaHCO3-P) and sodium hydroxide-extractable P (NaOH-P) fractions were reduced in early successional stages and increased in late stages. Compared to the primary forest, concentrations of P fractions in the four stages significantly decreased except for HCl-P, indicating that soil P supplements over the long-term did not return to primary forest levels. The results of related analysis also showed that NaHCO3-Pi levels were significantly related to available phosphorus. According to the path analysis coefficient, NaHCO3-Pi exhibited the highest effect on available P among eight P fractions; the indirect effects of other P fractions via NaHCO3-Pi were larger than those with other P fractions. Overall, this study suggests that soil P bioavailability gradually improved during natural vegetation restoration on clear-cut sites mainly through the increase of NaHCO3-P, where phosphorous is immediately available, and subsequently available phosphorus NaOH-P.

Soil microorganisms play an important role in biogeochemical cycles in terrestrial ecosystems. Increasing nitrogen (N) and phosphorus (P) deposition are likely to regulate microbial growth by altering soil nutrient availability in tropical forests, yet their impacts on microbial community structure and function between primary forests and secondary forests are not well understood. To investigate how nutrient availability affects microbial community structure and function in tropical forests, we measured soil phospholipid fatty acids and enzyme activities in a seven-year N and P fertilization experiment in two tropical montane rainforests, China. In N addition plots, fungal biomass, arbuscular mycorrhizal fungal biomass and fungi to bacteria ratio (F/B) decreased in the secondary forest, but had moderate changes in the primary forest. In P and N plus P addition plots, microbial biomass showed minor changes, but the F/B increased significantly in both forests. However, hydrolytic enzyme activities did not show a significant change in the secondary forest, while they decreased significantly in the primary forest. Microbial P limitation in the primary forest decreased under P addition and N plus P addition. Our findings suggest inconsistent responses of microbial community structure and enzyme activity to N and P additions in tropical soils depending on forest type.

Studies contrasting parasite prevalence and host-parasite community structure between pristine and disturbed environments will improve our understanding of how deforestation affects disease transmission and parasite extinction. To determine how infection rates of a common and diverse group of avian blood parasites (Plasmodium and Haemoproteus) respond to changes in avian host composition after mining, we surveyed 25 bird communities from pristine forests (two forest types: plateau and hillside) and reforested sites in Northeast Amazonia. Infection rates and both parasite and avian host community structure exhibited considerable variation across the deforestation gradient. In opposition to the emerging pattern of lower avian haemosporidian prevalence in disturbed tropical forests in Africa, we show that secondary forests had higher haemosporidian prevalence in one of the largest mining areas of Amazonia. The dissimilarity displayed by bird communities may explain, in part, the higher prevalence of Haemoproteus in reforested areas owing to the tolerance of some bird species to open-canopy forest habitat. On the other hand, deforestation may cause local extinction of Plasmodium parasites due to the loss of their avian hosts that depend on closed-canopy primary forest habitats. Our results demonstrate that forest loss induced by anthropogenic changes can affect a host-parasite system and disturb both parasite transmission and diversity.

Long-term (2009–2019) field studies of the CO2 fluxes over the Valday upland in north-western European Russia were performed in an old-growth spruce-dominated forest subject to the combined effects of climate change, bark beetle attacks and windfall events. The annual carbon uptake within the study area decreased from − 300 g C m−2 yr−1 in 2010–2011 to − 95 g C m−2 yr−1 in 2018 as a result of progressive tree mortality. However, mortality did not cause a significant reduction in specific ecosystem respiration. The respiration of the damaged forest was formed by efflux from soil (64.8%), living vegetation (15.5%), hotspots under dry standing trees (12.1%) and decomposition of woody debris (7.6%). High correlations between net ecosystem exchange and dry standing spruce stocks and average soil CO2 efflux were found. The decrease in the carbon sink was followed by a decline in evapotranspiration from 0.0142 ± 0.0003 g H2O m−2 s−1 for May–October 2010 to 0.0116 ± 0.0002 g H2O m−2 s−1 in 2018. We assumed that the decrease in carbon uptake was due to both the reduction in primary tree production and the decrease in the area of the unaffected stands. Our estimates show that an increase in tree mortality up to 27% of a stand area could turn an old-growth spruce forest into a net source of CO2. This should be taken into account when considering human-induced and climate-related effects on boreal forests.

Land-use and cover change reflects choices in natural resource governance. Despite heavy targets on the forest and woodland, the southwest Nigeria states have little quantitative information on the magnitude and direction of land-use change across the states. This drives unsustainable land management and deforestation. This study utilized vegetation sampling and enumeration, GIS mapping and analyses of base maps and multi-temporal Landsat imageries to generate current vegetation status and time-series land-use and cover change for the southwest Nigeria. The results suggest that the woody species density in the forest plots ranges from 512 to 1040/ha with mean density of about 770.67/ha and species diversity values range from 2.014 to 2.911. The woody species in the savanna woodland ranged from 624 to 1232/ha in density and species diversity varies between 1.189 and 2.737. Relatively fewer number of trees of larger diameter at breast height in forest and low number of species per family in savanna reflect the influence of selective forest logging and woodland degradation. The study area experienced a historical net deforestation rate of − 1.1% per annum between 1986 and 2016 with deforestation rate of the primary forest at − 3.3% between 1986 and 2016 and − 10% between 2006 and 2016. Savanna woodland grew 0.8% annually from 1986 to 2016. The states recorded net deforestation rate ranging from − 2.63 to − 7.41% between 2006 and 2016. Reforestation through exotic Teak and Gmelina plantation grew at 43% annually between 1986 and 2016.

Stress tolerance is the predominant strategy among the plant species that colonize the Brazilian rupestrian grassland (Campo rupestre) and is a response to edaphic conditions involving specific morphological and physiological adaptations. Motivated by the need to increase the efficiency in the production of seedlings, we experimentally evaluated whether these plant species are naturally limited in terms of optimum development and if they could have their survival and growth increased when cultivated under enhanced nutrient and water conditions and reduced iron concentration. To experimentally test this hypothesis, we cultivated seedlings of nine plant species in six distinct substrates for 150 days. The percentage of seedling survival had great variation among species (ranging from 40 to 100% survival). Eight out of the nine studied species showed higher growth and higher biomass accumulation as well as greater investment in aerial parts when grown in nursery or organic substrate (up to 10 times greater than the control treatment). This study provides evidence that these species also present reversible adjustment to cope with the poor soil conditions and are able to improve their performance in more fertile soils. Thus, seedling production for the restoration of ironstone rupestrian grasslands can be more efficient.

ContextComplex interactions between societies and their environment have shaped landscapes across Europe over centuries. Therefore, taking a historical perspective can be important when designing new forestry policy and management activities.ObjectivesThis perspective aims to improve our appreciation of how a better historical understanding of landscapes can increase our understanding of current conditions and inform current and future policy and practice. I provide a perspective on land-use legacies and forest change, with a particular emphasis on landscapes, and using the example of forestry in the United Kingdom.MethodsFor this purpose, I undertook a comprehensive review of scholarly forestry literature and of relevant policy and legal documents in the UK, covering the last 100 years.ResultsThis brief review of the dynamics of forest landscapes in the UK over the last 100 years, shows that certain decisions, policies and management activities had major effects on the landscape, especially in terms of landscape patterns and species distribution, constraining it until today. Historic research investigated some of these legacies, leading to real change in policy and management, including a Broadleaved Policy, an Ancient Woodland Inventory, habitat restoration, habitat network and rewilding schemes. Research on past experiences of Dutch Elm disease in the UK and of similar outbreaks in other countries have guided responses to today’s tree pest/disease outbreaks and plant trade decisions.ConclusionA better appreciation of past decisions and activities, especially in forestry, helps to anticipate landscape legacy effects and potential cross-scale interactions of new policies and practices. It may also help to better justify and negotiate new decisions and long-term planning among multiple actors.

Rapid economic development has led to high rates of deforestation and widespread alteration of land cover in many regions in China, where many primary forests have been replaced by secondary and plantation forests. Therefore, we aimed to determine differences in bird community diversity and structure between three forest types. We assessed differences in species richness, phylogenetic and functional diversity and community structure of bird communities in primary, secondary and plantation forests. Data was collected over four meteorological seasons from bird communities in a nature reserve in the Hengduan Mountains, China. We found that functional and phylogenetic diversity in secondary forest were significantly greater than in primary forest, while species richness was not significantly different. Thus, simple metrics (i.e. species richness) may not be sufficient to assess forest conservation value. We suggest that it is necessary to use varied diversity metrics that incorporate species’ similarities and differences. It also appears that secondary forests play an important role in the maintenance of studied bird biodiversity. The results of community structure analyses show that the habitat filter was strongest in the primary forest, leading to primary forest species being lighter in weight, shorter in body length, and with longer tarsometatarsus. These species were specialized and forest-dependent, reflecting the value of primary forests as an irreplaceable habitat type for several species after nearby forests are degraded.

Throughout Southeast Asia, removal of old growth forests coincides with rapid expansion of secondary forest landcover. Increasing evidence suggests that secondary forests can contribute to conservation of forest species. The effects of deforestation and subsequent reforestation by secondary vegetation on forest biotas vary geographically, and local data are needed to understand the potential role such forests may play in conservation. In the Philippine Archipelago, a globally distinct biota is coupled with severe deforestation. Focusing solely on old growth forest preservation may no longer be a feasible strategy of achieving conservation goals on islands that have lost the majority of old growth tracts. The potential of Philippine secondary forests to provide habitat for the endemic component of animal communities is not well known. We studied frugivorous butterflies, a common indicator taxon, at a limited spatial scale in Mount Kanlaon Natural Park, Negros Occidental, Philippines. We compared the butterfly communities of three contiguous forest types across a small spatial scale: disturbed secondary forest, regenerating secondary forest, and old growth forest. Hierarchical cluster analysis and NMDS ordination indicated high similarity between communities, though the close proximity of sampling areas may have influenced this similarity. Significant differences between secondary and old growth sites were detected by permutational MANOVA. Endemic butterfly species were abundant in both secondary forest types, and some endemic species were significantly more abundant in secondary forests compared to old growth. These results indicate endemic frugivorous butterflies utilize regenerating habitats at close proximity to intact forest, and provide evidence that secondary forests in the Philippines can contribute to the conservation of endemic components of butterfly communities. However, further study is needed to fully characterize the contribution of regenerating forests, broadly, to conservation strategies in the Philippines.

Forests play one of the most important roles in the hydrological cycle; as a result, knowledge about the water relations in forest areas should be of great importance in the context of global change. In Poland, the level of groundwater in forest areas has been decreasing for several decades, which negatively affects forest stands. To prevent this, activities have been carried out to increase water resources. Therefore, there is a need to develop a method for prioritizing the locations of retention investment projects. While searching for simple methods to achieve this goal, it was assumed that retention facilities should be located first in the partial catchments with the greatest possible retention capacities. This value, which is called the potential retention of the catchment, can be calculated using the CN parameter, which is used in the soil conservation service–curve number (SCS–CN) method. The CN parameter contains information on the type of land cover, the type of soil, and the moisture content. The source of the obtained land-use data was the Corine Land Cover (CLC) database, which was developed by the European Environment Agency for the area of the European Union. The analyses were carried out on the forest catchment of the Łutownia River, which is located in the Białowieża Primeval Forest.

Despite substantial investment in prescribed burning for biodiversity conservation there has been surprisingly little demonstration of its efficacy in achieving intended conservation aims for fauna. In the case of northern Australia’s threatened mammal fauna, most studies have reported negative responses to fire. We used satellite-derived fire scar imagery and small mammal survey data to compare fire regimes and threatened mammal abundance before and after implementation of broad-scale prescribed burning in north-western Australia. Specifically, we tested: (1) whether prescribed burning was effective in changing fire regimes; (2) whether all mammal species and functional groups responded to prescribed burning; and (3) what regional fire and environmental variables explained changes in mammal status. Low-intensity, patchy prescribed burning in the early dry season reduced the extent of high intensity late dry season wildfires. In sandstone habitats the abundance of all mammals, and the large marsupials and specialist rodent functional groups, increased concurrently with early dry season prescribed burning. All mammals and the small dasyurid functional group in woodland habitats also increased during this period. Early dry season prescribed burning extent was the strongest explanatory variable for mammal increases. Early dry season burning was also the strongest explanatory variable for woodland mammal abundance, but these mammals also had a positive association with extent of large patches of old growth vegetation (> 4 years since fire). Generalist rodents did not respond to prescribed burning and two other species declined following prescribed burning in one habitat. Generalist rodents and the two declining species had a negative association with extent of late dry season fire and a positive association with old growth vegetation (interacting with patch size). These results suggest an increased application of patchy early dry season prescribed burning of up to ca. 30% of the area will benefit positive fire responder species of threatened mammals including large specialist rock/arboreal rodents and most marsupial species. For mammals such as generalist terrestrial rodents with predominantly negative associations with fire, managers should seek to increase the size and extent of old growth vegetation.

In wolves Canis lupus, scent marking plays an important role in territory defence. In Europe, studies on patterns of scent marking in wolves have mostly been conducted in mountains or primeval forests, but since these areas are characterised by low human activity, the impact of people on this behaviour has been neglected. We conducted a study that combined genetic methods with an analysis of the spatial distribution of wolf territory markings in lowland managed forests with high human activity. We found that scent markings are deposited by all members of wolf family groups. Wolves most intensively marked crossroads and their vicinity, especially on roads only accessible for four-wheel drive cars. Our study provides further evidence that crossroads of forest roads play a crucial role in wolf scent marking. The results of our study may be useful during inventories of wolf populations based on collecting indirect signs of their presence or non-invasive genetic sampling.

Butterflies are among the most colourful organisms in the world and colour plays a central role in many of their life-history strategies. However, the efficacy of coloration strategies in these and other animals could be affected by sudden environmental changes, including anthropogenic disturbances such as habitat loss and fragmentation. Here we investigate the effect of forest disturbance gradients on the colours of fruit-feeding butterflies in the Amazon Rainforest. The disturbance gradients tested represented habitat-size (continuous primary forests versus forest fragments of 1, 10 and 100 ha) and succession gradients (continuous primary forests, 30 year old secondary forests, and three year old early successional forests). Using digital image analysis, we obtained intrinsic measures of butterfly colour patches corresponding to hue, saturation, brightness, in addition to measures of the contrast among patches and of the overall wing-colour diversity corresponding to 220 individuals, belonging to 60 species. Our results showed that butterflies in the secondary forest and continuous primary forest are more colourful than those found in early succession and fragments of forests. Individuals occurring in forests of early succession showed higher average values of hue and saturation, but lower brightness. Accompanying changes in colour composition, wing-colour diversity among species was lower in human-disturbed habitats, such as those of early forest succession and secondary forest. Forest fragments have smaller effects on butterfly colour composition, indicating that well-structured forest habitats can house butterfly assemblages with more diverse phenotypic features and colours. We show how high deforestation rates in recent years is linked with negative changes in functional coloration strategies (e.g. camouflage, warning colours), something that has to date been poorly explored or demonstrated for butterflies. Specifically, human interference has apparently placed butterflies under strong selection for lower diversity in their colours and range of defensive strategies. Those species that are most colourful are the first to be locally extinguished, likely due to removal of native vegetation and increased exposure to predators, and more broadly owing to inhospitable environmental conditions. This illustrates an accelerated loss of local fauna and a “discolouration” of the Amazonian butterflies due to anthropogenic impacts.

The climate and altitude play an important role in composition and distribution of Himalayan vegetation. Hence this study was aimed to understand the influence of altitude and slope aspect on diversity, regeneration, and structure of some temperate forests of Garhwal Himalaya. The maximum mean tree density (627 ± 27.04 trees ha−1) was recorded on southwest facing aspect for Rhododendron arboreum-Quercus semecarpifolia association whereas, minimum (555 ± 43.11 trees ha−1) on northwest aspect for Quercus semecarpifolia-Abies spectabilis association. However, highest mean total basal cover value (99.84 ± 10.9 m2 ha−1) was found on northwest aspect and lowest (79.15 ± 12.9 m2 ha−1) on southeast facing aspect for Q. semecarpifolia-A. spectabilis association. The greater mean Shannon Index values (i.e., trees, 1.40 ± 0.05; shrubs, 1.67 ± 0.05 and herbs, 2.48 ± 0.05) were recorded for R. arboreum-Q. semecarpifolia (CTI), Q. semecarpifolia-A. pindrow (CTII) and Q. semecarpifolia-A. spectabilis (CTIII), respectively, whereas, lower value (trees, 0.59 ± 0.17) for Q. semecarpifolia-A. spectabilis (CTIV), shrubs (1.44 ± 0.16) and herbs (2.0 ± 0.12) for R. arboreum-Q. semecarpifolia association. The tree species like Quercus semecarpifolia, Rhododendron arboreum, Abies spectabilis were found widely distributed in the study area. The regeneration study revealed that southwest facing aspect community vegetation experienced additional threat of extinction by representing 26.67% species as not regenerating. Overall a reverse ‘J’ shaped structure was obtained for all studied communities representing higher densities on lower dbh classes while, The Q. semecarpifolia-A. spectabilis (CTIII) exhibited maximum total basal cover value on higher dbh classes (i.e., 50–70 cm). Henceforth, it could be concluded that the forest community growing between 2800–3400 m asl was comparatively mature and old growth, and could be recommended for conservation purposes.

Urban areas are increasing globally causing fragmentation and loss of habitats for many forest dwelling species. At the same time new habitats are created, which may be exploited by species with a broad ecological tolerance. Bats form the largest mammal group living in cities in Central Europe. Species diversity might be higher in some cities compared to rural areas. Yet, habitat-specialists struggle with rapid landscape change and urban development. The Bechstein’s bat Myotis bechsteinii is dependent on old growth deciduous forests that supply tree cavities to roost in. The use of small home ranges requires high prey abundance around roosts. Despite their habitat specialization we identified two Bechstein’s maternity colonies within the metropolitan area of Frankfurt/Main (Germany). The colonies numbered 25 and 31 adult females respectively. We radio tracked individuals from both colonies (n = 14) and compared their habitat use to that of females (n = 79) of 11 colonies from rural woodlands. We identified a total of 29 roosts used by the two maternity colonies during summer. Roost choice of the urban forest colonies was similar to the rural forest colonies with a preference for oak trees with woodpecker holes. The distances between roosts were similar between urban and rural colonies. Habitat selection was strongly towards old forest patches. We emphasize the importance of the persistence of old forest islands within urban areas to support remaining bat colonies with a network of bat areas, similar to the important bird areas (IBAs). Specialized species that fail to adapt to the rapid changes may survive within the urban environment relying on old forest patches.

Legacy attributes from land-use history have lingering effects on soil and its below-ground components undergoing succession that has important consequences for regenerating tropical secondary forests. Yet, even landscapes of similar origins with analogous land-use histories have exhibited differing routes of forest recovery with different outcomes. There is increasing evidence that tree species-generated soil microbial heterogeneity is an important factor in facilitating regeneration, particularly nitrogen (N)-fixing tree species. However, it is unclear how land-use history influences the soil microbiome of important N-fixing plants developing under these conditions; at different life stages of N-fixing plant development; and how this compares to a primary forest. We examined differences in composition of the soil bacterial and fungal communities and their determinants (i.e. soil environmental factors) associated with large-, medium-, and small-sized Pentaclethra macroloba trees in a primary forest and in a 23-year-old secondary forest with contrasting land-use histories. We show that as Pentaclethra increases in size (and/or age), the soil microbiome associated with Pentaclethra also changes, and that these soil microbiomes can become similar even when developed in soils of contrasting land-use histories. We found that soil NH4+ and NO3− explained 61% of the variation in the soil bacterial community composition of small trees between the primary and secondary forest. This highlights the importance of inorganic N during tree soil microbiome development in contrasting land-use history of soils. Our findings suggest that legacy effects on may be mediated through size (and/or age) of Pentaclethra and its associated soil microbiome.

Context Hedgerows are highly important for maintaining the biodiversity in deforested landscapes. Especially for habitat specialists such as several forest plants they can provide important refuge habitats. Objectives This study aims to examine whether there is an extinction debt for forest plants in hedgerows. Methods In a study area in Northern Germany that had lost 47% of the hedgerow network over the past 120 years, hedgerows were mapped for the presence of forest vascular plants. In a multi-model approach, we compared the explanatory power of present and historical landscape variables and habitat quality on diversity patterns. Results The change in landscape configuration had no effect on the species richness of forest plants in hedgerows, i.e. there was no sign of an extinction debt. The best explanatory variable was the hedgerow width with more species found in wider hedgerows. This demonstrates the importance of including local habitat variables in the study of extinction debt. For ancient woodland indicator species models including both the landscape configuration and habitat variables were superior to simple models. The best models included the historical distance to the nearest forest, suggesting an extinction debt. Counterintuitively, a high density of hedgerows had a negative influence on species richness, most likely because hedgerows are narrower in areas with higher densities due to land-saving measures by farmers. There was also a negative correlation between hedgerow density and the hedgerow proximity to forests. Conclusions The effects of important covariates may obscure species-area relationships and undermine extinction debt analyses.

Among vertebrates, amphibians currently have the highest proportion of threatened species worldwide, mainly through loss of habitat, leading to increased population isolation. Smaller amphibian populations may lose more genetic diversity, and become more dependent on immigration for survival. Investigations of landscape factors and patterns mediating migration and population genetic differentiation are fundamental for knowledge-based conservation. The pond-breeding northern crested newt (Triturus cristatus) populations are decreasing throughout Europe, and are a conservation concern. Using microsatellites, we studied the genetic structure of the northern crested newt in a boreal forest ecosystem containing two contrasting landscapes, one subject to recent change and habitat loss by clear-cutting and roadbuilding, and one with little anthropogenic disturbance. Newts from 12 breeding ponds were analyzed for 13 microsatellites and 7 landscape and spatial variables. With a Maximum-likelihood population-effects model we investigated important landscape factors potentially explaining genetic patterns. Results indicate that intervening landscape factors between breeding ponds, explain the genetic differentiation in addition to an isolation-by-distance effect. Geographic distance, gravel roads, and south/south-west facing slopes reduced landscape permeability and increased genetic differentiation for these newts. The effect was opposite for streams, presumably being more favorable for newt dispersal. Populations within or bordering on old growth forest had a higher allelic richness than populations in managed forest outside these areas. Old growth forest areas may be important source habitats in the conservation of northern crested newt populations.

In the absence of primeval floodplain forests, near-natural remnants are key references for close-to-nature forestry and nature conservation. Old-growth forest characteristics (OGCs) were quantified in 16 managed (rotation or selection) and abandoned semi-natural floodplain forests by taking snapshot inventories of structural features. Principal component analysis revealed a short gradient from closed-canopy managed stands dominated by large trees (mainly oaks) and hornbeams, with less deadwood, to abandoned older stands with more gaps, very large trees and different kinds of deadwood. All the studied forests are mainly in the early and late biostatic phases of forest development, with innovation and degradation phases almost completely absent. Results showed that selection forests had significantly more very large trees compared to rotation stands. The difference in structure between abandoned selection stands and abandoned rotation stands was more pronounced than in their counterparts that are still managed. Based on diameter distribution and the amount of very large trees and deadwood, abandoned selection stands were closest to the structure of natural forests. Selection forests may recover certain OGCs more rapidly than rotation forests. We concluded that after 100–150 years of homogenising rotation forestry, OGCs are slow to develop in just 25 years of non-intervention. Based on our results, we recommend: (i) an increase in the rotation cycle with selective logging in order to restore and maintain OGCs in managed rotation forests and (ii) total abandonment in certain well-preserved, near-natural forests with natural flooding regimes. However, the failure of oak to regenerate naturally remains a challenge.

Given the short time-frame to limit global warming, and the current emissions gap, it is critical to prioritise mitigation actions. To date, scant attention has been paid to the mitigation benefits of primary forest protection. We estimated tropical forest ecosystem carbon stocks and flows. The ecosystem carbon stock of primary tropical forests is estimated at 141–159 Pg C (billion tonnes of carbon) which is some 49–53% of all tropical forest carbon, the living biomass component of which alone is 91–103% of the remaining carbon budget to limit global warming to below 1.5 degrees above pre-industrial levels. Furthermore, tropical forests have ongoing sequestration rates 0.47–1.3 Pg C yr−1, equivalent to 8–13% of annual global anthropogenic CO2 (carbon dioxide) emissions. We examined three main forest-based strategies used in the land sector—halting deforestation, increasing forest restoration and improving the sustainable management of production forests. The mitigation benefits of primary forest protection are contingent upon how degradation is defined and accounted for, while those from restoration also depend on how restoration is understood and applied. Through proforestation, reduced carbon stocks in secondary forests can regrow to their natural carbon carrying capacity or primary forest state. We evaluated published data from studies comparing logged and unlogged forests. On average, primary forests store around 35% more carbon. While comparisons are confounded by a range of factors, reported biomass carbon recovery rates were from 40 to 100+ years. There is a substantive portfolio of forest-based mitigation actions and interventions available to policy and decision-makers, depending on national circumstances, in addition to SFM and plantation focused approaches, that can be grouped into four main strategies: protection; proforestation, reforestation and restoration; reform of guidelines, accounting rules and default values; landscape conservation planning. Given the emissions gap, mitigation strategies that merely reduce the rate of emissions against historic or projected reference levels are insufficient. Mitigation strategies are needed that explicitly avoid emissions where possible as well as enabling ongoing sequestration.

Soil-emitted N2O contributes to two-thirds of global N2O emissions, and is sensitive to global change. We used DayCent model to simulate major plant–soil N cycling processes under different global change scenarios in a typical temperate mixed forest in north-eastern China. Simulated scenarios included warming (T), elevated atmospheric CO2 concentration ([CO2]) (C), increased N deposition (N) and precipitation (P), and their full factorial combinations. The responses of plant–soil nitrogen cycling processes including net N mineralization, plant N uptake, gross nitrification, denitrification and soil N2O emission were examined. Concurrent increase of elevated [CO2] and N deposition displayed most strong interactive effects on most fluxes. Using the results from experimental studies for evaluation, simulation uncertainty was highest under elevated [CO2] and increased precipitation among the four global change factors. N deposition had a fundamental impact on soil N cycle and N2O emission in our studied forest. Despite forest soil acting as a N sink for added N, scenarios which included increased N deposition showed higher cumulative soil N2O emissions (summed up from 2001 to 2100). In particular, the scenario which included T, P, and N had the largest cumulative soil N2O emission, which was a 24.4% increase over that under ambient conditions. Our study points to the importance of the interactive effects of global change factors on plant–soil N cycling and the necessity of multi-factor manipulation experiments.

Variation in soil nutrient availability can influence the functional traits and performance of tree species in a forested landscape. We tested this hypothesis by studying the variations in leaf-traits, and N- and P-resorption efficiencies of a few evergreen (Myrica esculenta, Rhododendron arboretum and Lithocarpus dealbatus) and deciduous (Quercus griffithii, Engelhardtia spicata and Lyonia ovalifolia) tree species growing in montane subtropical old-growth and regenerating forests of Meghalaya, northeast India, varying in their soil characteristics. Trees of the old-growth forest stand, having greater soil total N and P, proved to be much efficient in their foliar nutrient resorption (mean = 42.0% for N and mean = 82.1% for P) and showed higher leaf nutritional quality compared to the regenerating forest stand. Deciduous species had greater N-resorption efficiencies (45.3–49.7%) than the evergreen species (23.6–56.9%) in the old-growth stand. However, in the regenerating stand, the evergreen species were better at resorbing both N (30.6–55.9%) and P (67.9–76.4%) from their leaves than the deciduous species (23.2–40.9% for N and 33.2–52.0% for P). Overall, phosphorus was the limiting nutrient for growth in both the functional groups, with relatively low concentrations in the soils of the two forest stands. The evergreen and deciduous trees in the old-growth forest are found to tightly conserve nutrients with higher leaf N and P concentrations and higher N- and P- resorption efficiencies than the regenerating forest stand. The study clearly indicates that soil fertility has profound effect on the internal nutrient cycling of evergreen and deciduous tree species.

Luyssaert et al.1 reported that unmanaged, old-growth forests continue to sequester atmospheric carbon (C) at a rate of 2.4 ± 0.8 Mg C ha–1 yr–1 for stand ages exceeding 200 years. This claim was based on an analysis of net ecosystem productivity (NEP) and other C flux data from temperate or boreal forest plots compiled from published studies and databases. Their conclusions and quantitative estimates are widely cited and essential in the debate on the role of forests in climate mitigation. Thus, it is important to discuss the validity of these estimates.Their conclusion was surprising given that such forests were thought to be C neutral2. Using data from several different viewpoints (for example, global net land flux, soil C accumulation rate, N demand to sustain C accumulation) and a re-analysis of the data provided by Luyssaert et al.1, we find evidence that the forest NEP values reported in the paper are markedly overestimated. Our analysis suggests that NEP is only 1.6 ± 0.6 Mg C ha–1 yr–1 for forests more than 200 years old, or about one-third less than the value reported by Luyssaert et al. Moreover, comparisons of net primary production (NPP) and heterotrophic respiration (Rh) suggest that some old unmanaged forests might serve as C sources. These inconsistencies bring into question the value of the NEP flux data given in Luyssaert et al.1 and their conclusion that unmanaged old-growth forests are important C sinks.

Logging and human-induced conversion of natural forests into agricultural areas are major drivers of biodiversity loss in the tropics. Anuran larvae can be highly diverse, can reach high biomass and can play important roles in tropical streams; yet, compared to the adult frog communities, relatively little is known about how larval communities respond to disturbance. Information on larvae is highly relevant for amphibian conservation because larvae represent direct evidence of breeding and thus provide a good indicator of species persistence in disturbed habitats. We studied tadpole assemblages in Ranomafana, southeastern part of Madagascar, in streams in a disturbed forest (previously logged forest), at “forest edge” (streams embedded in matrix nearby forest blocks), and compared these to communities in a primary forest. We sampled tadpoles at the microhabitat level (“pools” and “riffles”) in 9 streams. We recorded 27 species with a maximum of 17 species/stream recorded at edge. The three habitats harbored different assemblages, but, as could be expected, more similarities existed among forest habitats than between forest and non-forest habitats. The most and the least diverse communities were recorded at edge and in the disturbed forest, respectively. Assemblages were dominated by one generalist species, and changes in communities were mostly driven by changes in forest specialists, which either decreased in disturbed forest or were replaced by edge specialists outside forest. Although species richness varied, relative abundances were maintained among habitats, suggesting potential compensatory mechanisms in tadpole biomass. Community structure changed at the microhabitat level: pool environments usually harbored relatively higher species richness and abundance than riffles. Our study highlights the relevance of edge habitats for maintaining amphibian diversity and the pronounced negative effects of past logging activities on tadpole communities. Given the diverse roles of tadpoles in streams, changes in community structure potentially affect critical stream ecosystem processes. The study has strong implications for designing buffer zones around protected areas.

Brazil contains two-thirds of remaining Amazonian rainforests and is responsible for the most Amazon forest loss. Primary forest loss in the Brazilian Amazon has declined considerably since 2004 but secondary forest loss has never been quantified. We use a recently developed high-resolution land use/land cover dataset to track secondary forests in the Brazilian Amazon over 14 yr, providing the first estimates of secondary forest loss for the region. We find that secondary forest loss increased by (187 ± 48)% from 2008 to 2014. Moreover, the proportion of total forest loss accounted for by secondary forests rose from (37 ± 3)% in 2000 to (72 ± 5)% in 2014. The recent acceleration in secondary forests loss occurred across the entire region and was not driven simply by increasing secondary forest area but probably a conscious preferential shift towards clearance of a little-protected forest ecosystem (secondary forests). Our results suggest that secondary forests loss has eased deforestation pressure on primary forests. However, this has been at the expense of a lost carbon sequestration opportunity of 2.59–2.66 Pg C over our study period. Deforestation in the Brazilian Amazon affects both older (primary) and younger (secondary) forests. This study finds that most forest loss over the period 2008–2014 was from secondary forests and that the almost 190% rise in deforestation buffered losses from primary forests.

Species richness and composition of macrofungi on huge fallen trunks of spruce (Picea abies) were monitored at a model old-growth forest locality, Boubinský prales virgin forest (Czech Republic). Using detailed survey of all macrofungal groups based on fruit bodies, 168 species were recorded on 33 trunks with a diameter of 100–150 cm, which is a very high species richness. Individual trunks were inhabited by 6–32 species. The number of species per trunk was positively correlated with increasing tree cover, medium decay stages, and decreasing altitude. The species-richest groups were resupinate fungi with annual basidiomata and fleshy saprotrophic fungi. Species composition on particular trunks was significantly influenced by percentage of bark cover, altitude, and decay stage and to a lesser degree also by percentage of trunk contact with the soil and cover of mosses, trees, and shrubs. Resupinate fungi and fleshy saprotrophs were distributed along the entire decay gradient. Most polypores prevailed in early decay stages. Mycorrhizal agarics were associated with the latest stages. The presence of dominant species Fomitopsis pinicola had a low effect on the composition of other fungal species on the same trunk, whereas Phellinus nigrolimitatus had a significant effect. The monitoring revealed 71% of species known at the locality from spruce, and 45 species new to the locality, especially those with inconspicuous fruit bodies. The previously published field survey was more efficient for capturing rare species with larger fruit bodies. Both methods should be combined during mycobiota inventories.

The disturbance regime of mountain spruce–beech temperate forests has not yet been sufficiently elucidated. We hypothesized that spruce and beech express completely different disturbance histories and behavioural strategies, potentially causing exceptionally complex disturbance regimes. We further hypothesized that the spontaneous development of mountain forests can temporarily result in a simplification of the forest's spatial structure. We wanted to discover how the disturbance history and growth plasticity of the main tree species differ, and whether some old managed forests arose from primeval forest remnants. We compared dendrochronological records of the unmanaged Boubin Primeval Forest and 30 sites with current forestry records. Using this comparison, we categorized all sites into three categories. In the disturbance history of all evaluated forest sites, there was clear evidence of the presence of severe disturbances in the nineteenth century. However, the regeneration of beech was more continuous and less dependent on the presence of severe disturbances than the regeneration of spruce, which depended on the presence of severe disturbances of low frequency. Human-induced changes at some sites were manifested in changes in the initial growth of both species and disrupted their mutual competition and also led to a higher growth plasticity of beech. Despite human impacts in the region since the end of the nineteenth century, about 30% of analysed trees were older than the severe disturbances in the nineteenth century; therefore, some studies sites preserved the characteristics of primeval forest. Our results revealed three main forest development trajectories since the end of the nineteenth century.

Seed distribution and deposition patterns around parent trees are strongly affected by functional traits and therefore influence the development of plant communities. To assess the limitations of seed dispersal and the extent to which diaspore and neighbouring parental traits explain seed rain, we used a 9-year seed data set based on 150 seed traps in a 25-ha area of a temperate forest in the Changbai Mountain. Among 480,598 seeds belonging to 12 families, 17 genera, and 26 species were identified, only 54% of the species with mature trees in the community were represented in seeds collected over the 9 years, indicating a limitation in seed dispersal. Understory species were most limited; overstory species were least limited. Species with wind-dispersed seed had the least limitation, while the lowest similarity in species richness was for animal-dispersed species followed by gravity-dispersed species; fleshy-fruited species had stronger dispersal limitations than dry-fruited species. Generalized linear mixed models showed that relative basal area had a significant positive effect on seed abundance in traps, while the contribution of diaspore traits was low for nearly all groups. These results suggest that tree traits had the strongest contribution to seed dispersal and deposition for all functional groups examined here. These findings strengthen the knowledge that tree traits are key in explaining seed deposition patterns, at least at the primary dispersal stage. This improved knowledge of sources of seeds that are dispersed could facilitate greater understanding of seedling and community dynamics in temperate forests.

Natural spruce forests are restricted to the highest mountain ranges in the Czech Republic. Spruce is also the commonest tree species in managed forests. Owing to a massive decline of spruce forests in Central Europe, caused by recent climatic fluctuations and disturbances, the lichen diversity and species composition was compared between ten representative natural mountain old-growth forests in the Czech Republic and their counterparts in mature managed forests. The old-growth forests are characterized by a higher species richness, abundance, number of Red-listed species, functional, taxonomic and phylogenetic diversities. Plots with the highest species richness are situated in the Sumava Mountains, an area with a relatively low sulphur deposition in the past. Bioindication analysis searching for lichen indicators supported several species (e.g. Xylographa vitiligo, Chaenotheca sphaerocephala) and genera (e.g. Calicium, Xylographa) with a strong preference for old-growth forests. Analysis of lichen functional traits revealed a higher abundance of species with a vegetative reproduction in managed forests that may be explained by a higher efficiency in colonization by young successional stages. Lichens with stalked apothecia, pigmented ascospores and large ascospores are more frequent in old-growth forests. Our results are briefly discussed in terms of nature conservation, focusing on national refugees of old-growth forest species, biodiversity hot-spots, practical use of indicator species and representative measures for an evaluation of forest quality.

Widespread and continuing losses of tropical old-growth forests imperil global biodiversity and alter global carbon (C) cycling. Soil organic carbon (SOC) typically declines with land use change from old-growth forest, but the underlying mechanisms are poorly understood. Ecological restoration plantations offer an established means of restoring aboveground biomass, structure and diversity of forests, but their capacity to recover the soil microbial community and SOC is unknown due to limited empirical data and consensus on the mechanisms of SOC formation. Here, we examine soil microbial community response and SOC in tropical rainforest restoration plantings, comparing them with the original old-growth forest and the previous land use (pasture). Two decades post-reforestation, we found a statistically significant but small increase in SOC in the fast-turnover particulate C fraction. Although the δ13C signature of the more stable humic organic C (HOC) fraction indicated a significant compositional turnover in reforested soils, from C4 pasture-derived C to C3 forest-derived C, this did not translate to HOC gains compared with the pasture baseline. Matched old-growth rainforest soils had significantly higher concentrations of HOC than pasture and reforested soils, and soil microbial enzyme efficiency and the ratio of gram-positive to gram-negative bacteria followed the same pattern. Restoration plantings had unique soil microbial composition and function, distinct from baseline pasture but not converging on target old growth rainforest within the examined timeframe. Our results suggest that tropical reforestation efforts could benefit from management interventions beyond re-establishing tree cover to realize the ambition of early recovery of soil microbial communities and stable SOC. Electronic supplementary material The online version of this article (10.1007/s00248-019-01414-7) contains supplementary material, which is available to authorized users.

Cavity-nesting animals and their nest trees are linked in interspecific facilitation networks known as nest webs, which play key roles in forest function but vary across biomes and with human perturbation. We examined the composition, structure and function of nest webs between two endangered old-growth forests representing the last remnants of the ancient coniferous family Araucariaceae in South America: pewen (Araucaria araucana; Endangered) in temperate Chile (2010–2018), and Parana pine (Araucaria angustifolia; Critically Endangered) in subtropical Argentina (2006–2018). Pewen and Parana pine accounted for 30 and 9% of forest basal area, but only 2 and 5% of nesting cavities, respectively. Instead, cavity-nesting birds and mammals nested disproportionately in coexisting broadleaf trees. Species richness, interaction richness, and mean number of links per species were much higher in Parana pine forest than in pewen forest, but the two nest webs had similar levels of evenness and nestedness. Most secondary cavity-nesting species depended on cavities formed by decay in Nothofagus spp. (98% of nest cavities in pewen forest) or Apuleia leiocarpa (26% of nest cavities in Parana pine forest). An exception was the globally endangered Vinaceous Parrot, a Parana pine seed disperser, which made 50% of its nests in decay-formed cavities in Parana pine. To conserve the ecosystem functions of endangered Araucaria forests it is important to protect and recruit not only Araucaria trees but also a mix of broadleaf trees that can confer resilience to nest webs in the face of major disturbances.

The north-western Caucasus is exceptional in Europe because of its 1.3 million hectares of unmanaged ‘virgin’ forest. The Caucasus State Nature Reserve protects some 200,000 hectares, but contiguous areas are exposed to forest loss, fragmentation and degradation. Such an extensive region of virgin forest provides a unique opportunity to document diversity along key ecological gradients for an undisturbed system in Europe. Focusing on lichen epiphytes, we surveyed local diversity hot-spots along a 1200 m altitudinal gradient. Our main results are that: (a) species richness is enormously high in 1-hectare plots (between 233 and 358) representing a new baseline for Europe, (b) species composition differs substantially among plots with turnover increasing for difference in altitude. Cumulative species richness along the gradient was 597. More than a half of detected species had an affinity for, or were restricted to either the lower or the uppermost parts of the altitudinal gradient. However, this was related to differences in forest structure, rather than altitude per se. Species richness in plots increased significantly with the proportion of sparse/open forest. Length of an ecotone line, number of available tree and shrub species and number of dominant tree species also tend to increase species richness. These four variables had higher values at the lower and upper parts of the gradient, than at mid-altitudes, explaining a bimodal relationship of species richness with altitude. We conclude that loss of forest habitat at the lower and upper margins of the altitudinal gradient will cause the most significant decline in epiphytic lichen diversity.

Amazon rainforest is facing several threats due to anthropogenic activities causing loss of habitat, species, and ecosystem functions. However, several areas are being abandoned after anthropic use allowing secondary succession to occur, which can lead to the passive restoration of community parameters that have been lost. We aimed to investigate the effects of vegetation structure on dung beetle assemblages along a successional gradient in the western Amazon rainforest. Dung beetles were sampled and forest structure variables were measured using standardized protocols along primary, late secondary, and early secondary forests. We used a combination of generalized linear models and multivariate analyses to test for differences in assemblage composition and structure among successional stages and their relationships with vegetation variables. We found that primary forests have different species compositions from both late and early successional forests, with several species strongly associated with primary forests. Dung beetle abundance was higher in primary forests and influenced by variables describing the successional stages (i.e., tree density). Species turnover was the most important β-diversity component among and within each successional stage, with lower values in early secondary forests. Different pathways followed by secondary forests during forest succession may lead to increased species turnover similar to that found in primary forests. Biodiversity conservation will only work if secondary forests are allowed to recover to a late successional stage close to a primary forest stage. The loss of primary forests can cause an irreversible loss of species in need of conservation and with great functional importance in the Amazon rainforest.

Tropical understory birds have declined due largely to habitat loss and fragmentation. Here, we revisited a study conducted three decades ago and used artificial nests to examine depredation rates in a Costa Rican biological corridor. Using camera trap data, we compared potential nest predator detection rates at experimental tinamou ground nests in La Selva Biological Station and at sites in five local forest fragments. Nest predator detections were positively associated with landscape-scale core forest and distance away from forest edge, as well as with local-scale human trails, and negatively associated with primary forest compared to secondary growth. Twenty-two of 52 artificial nests were depredated, which was similar to previous research in the area. Mammalian and avian predators were common nest predators, but unknown predators (presumably snakes) were responsible for half of nests lost. Nests within La Selva core forest had lower probability of nest loss compared to fragments despite exhibiting higher predator detection rates. Yet other fragmentation covariates such as distance from forest edge, nest occurrence on human trails, or forest age were not associated with nest loss. We suggest that concentrated foraging is the underlying mechanism behind the community interactions that we observed. Community members exist in concentrated use areas within forest fragments, which results in heightened predator foraging rates and thus stronger interactions in fragments despite more predators encountering the nests in core forest. Fragmentation is a global phenomenon and we suspect that concentrated community use of limited resources is driving species to interact more strongly than in natural ecosystems.

The patch mosaic–development stage model posits the unity of patches and development stages in primeval temperate forests and links patchiness to the synchronized, coarse-scale canopy senescence, and breakup processes that initiate the demographic transition to new regeneration patches that then asynchronously progress through sequential development stages. Subtle structural differences and inconsistent transitions among development stages observed in primeval forests such as Oriental beech (Fagus orientalis Lipsky) set expected coarse-scale canopy senescence against observed, predominantly fine-scale canopy-gap dynamics. Applying a multi-scale approach to quantify the extent to which stages are characterized by the interspersion of neighborhoods of variously sized trees (i.e., patch types), we investigated patchiness and structural differences in nine Oriental beech stands classified into Initial, Optimum, and Decay stages. Differences among stages in patch type richness and composition occurred primarily at the finest scales and diminished rapidly with increasing scale. Most patch types were ubiquitous and the few patch types unique to a particular stage occurred at very low abundances. Patch types composed of advance regeneration were most prevalent in the Initial stage, but were absorbed into the matrix structure at scales > 500 m2. In all three stages, the most heterogeneous patch type encompassed > 90% of all trees at scales > 100 m2. To portray fine-scale dynamics resulting in similar patch type compositions and structures across development stages, we introduce and discuss the new patch mosaic–gap reabsorption model that avoids the unity of patch and “demographic” stage to focus instead on “structural” stages.

Species richness, diversity and abundance of bat fauna in Similipal Biosphere Reserve were studied during 2013–2015. Bats were surveyed by exploring the roosting sites and mist netting for 288 nights in primary forest, degraded forest, agricultural land and human habitation. A total of 21 species representing three species of frugivore bats and 18 species of insectivorous bats in seven families were recorded during the study, of which 152 individuals in 13 species were captured in mist nets. Species diversity and capture rate were recorded higher in primary forest. Vespertilionidae was reported as the most diverse family with five species, and Rhinolophus lepidus was reported to be the most abundant species with maximum capture rate during the study. As Similipal Biosphere Reserve is experiencing severe biotic pressure, it can be predicted that the structure and composition of bat fauna may be affected. The authors expect that their findings will be useful for future comparative studies to monitor the change over time and develop conservation plans.

Agroforestry systems are widely extolled as a biodiversity-friendly alternative to food and wood production. However, few studies on large-vertebrates in the tropics consistently support this assumption. In the Amazonian ‘arch of deforestation’, commodity cropland and pastures for beef production have relentlessly replaced native forests. Agroforestry should therefore be both economically profitable and a more wildlife-friendly land-use alternative. Here we assess the local abundance and habitat use by forest primates and ungulates in a landscape mosaic containing large areas of primary forest and teak (Tectona grandis) agroforestry. We focused on animals of these groups because they have similar day ranges and home ranges, and are at the same trophic level. We surveyed 12 transects in both of these environments, totalling 485 km walked. We recorded four ungulate (Tayassu pecari, Pecari tajacu, Mazama americana, and Tapirus terrestris) and seven primate species (Ateles chamek, Lagothrix cana, Sapajus apella, Saimiri ustus, Chiropotes albinasus, Plecturocebus cf. moloch and Mico cf. emiliae). We indicate the importance of a species-level approach to evaluate the contribution of agroforests to population persistence. Large-bodied atelids, which are ripe-fruit-pulp specialists, were never recorded in teak agroforest. Sakis were more common in primary forest, while the smallest faunivore-frugivores had similar sighting rates in both environments. Ungulates exhibited subtler differences in their use of space than primates, but their sighting rates and track counts indicated temporal niche partition. White-lipped peccaries and red brocket deer were the only ungulates more frequently recorded in primary forest areas. Teak agroforestry still harbours some large and midsized frugivores, which may contribute with some biotic ecosystem services if their patches are connected to primary tropical forests. However, teak agroforestry should not be used to justify population subsidies for all Amazonian forest vertebrate species, since at least some threatened species clearly avoid forest stands dominated by this fast-growing exotic tree.

In woodlands, land use legacy, but also present habitat management can influence biodiversity and ecosystem functions in various ways. However, little is known about how former and current land use interact in woodlands with different habitat continuity and tree age. The aim of this study was to investigate the impact of both habitat continuity and tree age on ground beetles. We performed a field study in the nature reserve “Lüneburger Heide” (Germany). The study area comprised ancient woodland embedded in a matrix of recent woodland. We defined four woodland types by combining ancient and recent woodland with young and old trees and analysed five replicate plots within each of the resulting four woodland types. Habitat continuity, tree age as well as the combination of both of these factors had no significant impact on ground beetle species diversity, abundance, biomass, and evenness with most woodland species occurring on near to all of the four types of woodland plots. Four species, however, showed a significant preference for one of the specified woodland types studied. Our findings provide evidence that all woodland-inhabiting ground beetles of this region are able to colonize new habitats in the continuous woodland matrix, at least, up until a distance of 2.3 km. We call for a heterogeneous woodland management and increasing habitat connectivity to protect both species with a preference for ancient woodland sites and/or old trees and those species which prefer early successional stages.

The deforestation has led to local loss of species and important ecosystem services performed by them, causing ecological and economic losses. It is proposed that the reforestation of such areas aims to reduce those impacts. However, particularly in the tropics, little is known about the real success of different types of reforestation in the recovery of the species, and especially of the population parameters. Here we evaluated whether different types of reforestations affect Trypoxylon (Trypargilum) lactitarse Saussure (Hymenoptera: Crabronidae) in terms of abundance, percentage of emergence, proportion of males, fluctuating asymmetry, and foraging capacity. We compared primary forest (control) data to data collected in five different habitats: pasture, secondary forest, and tree plantations of Teak, Ficus, and a mixture of native species. The abundance of T. lactitarse was higher in tree plantations than in pasture. However, among the analyzed parameters, Teak plantation presented lower emergence percentage and the majority of individuals born were males. The emerged females in this habitat showed higher asymmetry and lower foraging capacity. Ficus showed lower individual abundance and mixed plantation showed lower emergence percentage, with both plantation types showing higher male emergence. On the other hand, in secondary forest, the analyzed parameters did not differ in relation to the primary forest, being the habitat more efficient in relation to those with tree planting. The changes in population parameters of T. lactitarse in different reforestations and particularly on Teak monocultures were probably attributed to indirect effects, such as low food availability and inadequate environmental conditions.

An important factor controlling tree species diversity is conspecific density dependence (CDD). Adult trees associated with arbuscular mycorrhiza (AM) and ectomycorrhiza (ECM) can exhibit negative and positive CDD effects on conspecific recruitment, respectively. However, the extent to which these mycorrhizal associations affect spatial distributions of individual trees and their relative abundances within forests through CDD remains uncertain. We analysed changes in spatial correlations between adults and conspecific juveniles at different growth stages of five hardwood species in a 6-ha plot of an old-growth forest using a point pattern analysis. The clump sizes of large individuals were also evaluated using the Iδ index (a measure of individual dispersion) in 24 species. In two AM-associated species, juveniles were distributed at greater distances with increasing size or were always distributed at a distance from adults, resulting in small clumps of adults. In contrast, juveniles of two ECM-associated species were distributed close to adults during early or late growth stage, resulting in large clumps of adults. Juveniles of an ECM-associated species disappeared with increasing size, probably due to shade intolerance. In 24 tree species with large numbers of individuals within a plot, the relative basal area was related to both mycorrhizal type and maximum diameter, suggesting that the relative abundance of a species is largely related to its mycorrhizal associations and maximum plant size. This study strongly demonstrated that mycorrhizal associations play an important role in determining the spatial distribution patterns and community structure of tree species through CDD.