Intermediate Successional Stages Research Articles

Prevalence and composition of haemosporidians in an avian community from a World Heritage area: Associations with host foraging strata and forest regeneration

Forest regeneration is becoming a powerful tool to combat land conversion which covers 30 % of the Neotropical territory. However, little is known about the effect of forest regeneration on vector-borne diseases. Here, we describe the haemosporidian lineage composition across a successional gradient within an Atlantic Forest bird community. We test whether forest successional stages, in addition to host life history traits affect haemosporidian infection probability. We sampled birds at 16 sampling units with different successional stages between 2017 and 2018 within a forest remnant located in Antonina, Paraná, Brazil. We captured bird individuals using mist-nets, identified them to the species level, and collected blood samples to detect and identify Plasmodium and Haemoproteus lineages based on molecular analysis. We used a Bayesian phylogenetic linear model with a Bernoulli distribution to test whether the haemosporidian infection probability is affected by nest type, foraging stratum, and forest successional stage. We captured 322 bird individuals belonging to 52 species and 21 families. We found 31 parasite lineages and an overall haemosporidian prevalence of 23.9 %, with most infections being caused by Plasmodium (21.7 % of prevalence). The Plasmodium probability of infection was associated with forest successional stage and bird foraging stratum. Birds from the secondary forest in an intermediate stage of succession are more likely to be infected by the parasites than birds from the primary forests (β = 1.21, 95 % CI = 0.11 – 2.43), birds from upper strata exhibit a lower probability of infection than birds from lower foraging strata (β = -1.81, 95 % CI = -3.80 – -0.08). Nest type did not affect the Plasmodium probability of infection. Our results highlight the relevance of forest succession on haemosporidian infection dynamics, which is particularly relevant in a world where natural regeneration is the main tool used in forest restoration.

The puzzling ecology of African Marantaceae forests.

Marantaceae forests are tropical rainforests characterized by a continuous understory layer of perennial giant herbs and a near absence of tree regeneration. Although widespread in West-Central Africa, Marantaceae forests have rarely been considered in the international literature. Yet, they pose key challenges and opportunities for theoretical ecology that transcend the borders of the continent. Specifically, we ask in this review whether open Marantaceae forests and dense closed-canopy forests can be considered as one of the few documented examples of alternative stable states in tropical forests. First, we introduce the different ecological factors that have been posited to drive Marantaceae forests (climate, soil, historical and recent anthropogenic pressures, herbivores) and develop the different hypotheses that have been suggested to explain how Marantaceae forests establish in relation with other vegetation types (understory invasion, early succession after disturbance, and intermediate successional stage). Then, we review the underlying ecological mechanisms that can explain the stability of Marantaceae forests in the long term (tree recruitment inhibition, promotion of and resilience to fire, adaptive reproduction, maintenance by megaherbivores). Although some uncertainties remain and call for further empirical and theoretical research, we found converging evidence that Marantaceae forests are associated with an ecological succession that has been deflected or arrested. If verified, Marantaceae forests may provide a useful model to understand critical transitions in forest ecosystems, which is of particular relevance to achieve sustainable forest management and mitigate global climate change.

Differences in mixed‐species bird flocks across forest succession: Combining network analysis and trait‐based ecology related to the fast‐slow continuum

Abstract Secondary forests are increasingly important for biodiversity conservation and ecosystem functioning. Yet, we know little on how species interactions shift across the wide range of life history strategies in the context of forest succession, especially for non‐trophic animal social systems. Using data from mixed‐species flocks (hereafter MSFs) and life history and morphological traits from the ‘fast‐slow’ continuum, we utilized a novel combination of network theory and trait‐based ecology to examine the assembly of associations of MSFs among species with different fast‐slow strategies across stages of forest succession that exhibit different degrees of forest complexity. MSFs formed the most connected and cohesive network in the intermediate successional stage. In contrast, we observed the least connected and cohesive network in the early stage, and a strongly connected but intermediately cohesive network in the late stage. Fast species with smaller body size and mass, and larger clutch size, were gradually replaced by slow species during succession. Interspecific associations generally shifted from those among similarly fast species (early stage) to associations between fast and slow species (intermediate stage), and finally to those among similarly slow species (late stage). We suggest that vegetation complexity (e.g. tree size, height, diversity and canopy cover), related to the availability of resources and number of niches, shaped the network structure and functional composition of MSFs. Although the late successional forests play an irreplaceable role in protecting forest specialists (i.e. slow species), intermediate stage forests should be also protected, because the large‐sized networks formed by MSFs at intermediate stages can simultaneously conserve more species with varying ecological strategies. Read the free Plain Language Summary for this article on the Journal blog.

Woody species succession and spontaneous forest development in post-mining sites after coal mining in the Czech Republic

There is little information about long-term spontaneous forest development after industrial disturbances. A field study was done along the chronosequence of unreclaimed post-mining sites (12, 25, 32, 60 and 90 years old), developing by spontaneous succession in the northwestern Czech Republic. Initial stages of forest development (12- to 60-yr-old) were dominated mainly by silver birch (Betula pendula) goat willow (Salix caprea) and aspen (Populus tremula), Norway spruce (Picea abies) also established naturally in the intermediate stages of succession. A 90-yr-old site was close to the expected climax forest with 21 woody species dominated by European oak (Quercus robus L.), supplemented by beech (Fagus sylvatica). The youngest and oldest sites were more diverse and richer sites in woody species than others, as expressed by the Shannon-Weiner and Simpson indices. Conversely, spatial heterogeneity (aggregation) increased with increasing age; however, it became lower at the age of 90 years. Woody species in the understory were more diverse than in the tree layer. Overall, our study found that spontaneous processes can lead to the development of the late-successional forest in fewer than 100 years in Central Europe.

Food falls in the deep northwestern Weddell Sea

When pelagic organisms die and fall onto the deep-sea floor they create food falls, i.e., parcels of organic enrichment that subsidize deep benthic scavenging communities. The diversity and quantities of food falls remain unstudied for many ocean regions since they are stochastically deposited and rapidly scavenged. The Southern Ocean habitat supports large populations of megafauna but few food falls have been documented. To investigate the diversity and quantity of food falls in the northwestern Weddell Sea, we analyzed 8476 images from the deep seafloor that were captured during the expedition PS118 on RV Polarstern in 2019 by the camera system OFOBS (Ocean Floor Observation and Bathymetry System). OFOBS was towed 1.5 m above the seafloor along five transects (400 to 2200 m seafloor depth) east of the Antarctic Peninsula. We observed the carcasses of one baleen whale, one penguin, and four fish at depths of 647 m, 613 m, 647 m, 2136 m, 2165 m, and 2112 m, respectively, as well as associated scavenging fauna. To the best of our knowledge, we describe here the first in situ observations of deep-sea food falls for penguins and fish in the Southern Ocean. While the whale carcass seemed in an intermediate successional stage, both the penguin and the fish were likely recently deposited and three of the fish potentially resulted from fishery discards. Our relatively small data set suggests that a diverse array of food falls provide nutrients to the slopes of the Powell Basin.

Repeated survey along the foreland of a receding Norwegian glacier reveals shifts in succession of beetles and spiders

Glacier forelands provide important sites to study climate-forced ecological succession because a chronosequence is apparent along a single valley. However, most studies of invertebrate succession in forelands provide a single snapshot of community assemblage patterns. With glaciers retreating rapidly worldwide, it is important to begin re-surveying community composition and assessing changes in relation to new terrain revealed by the retreating ice. In this study, we repeat a survey of spiders and beetles along the glacier foreland of the sub-alpine glacier Austerdalsbreen in western Norway, 15 years after an initial assessment in 2004, during which time the glacier has retreated 400 m. Invertebrates were sampled in 18 sites that represent a terrain age gradient of approximately 10–250 years since glacier recession. Forty spider species and 70 beetle species were identified, constituting the richest record in Nordic glacier forelands for these two taxonomic groups. Furthermore, three distinctive stages of succession were determined using TWINSPAN and NMDS: (1) a pioneer colonizer stage; (2) an intermediate successional stage; and (3) two late colonizer stages. Additionally, a species group of omnipresent species was identified. The transition from pioneer stage to early succession was characterized by a high degree of taxonomic replacement. Compared to the findings in 2004, we found that the composition of species groups on relatively old terrain is becoming more similar, while the differences between the species groups on the younger terrain are widening. This discrepancy is discussed in relation to climate warming, which potentially facilitates faster establishment of vegetation and early successional invertebrates and may therefore increase competition stress for cold-adapted pioneer species.

Different variations in soil CO2, CH4, and N2O fluxes and their responses to edaphic factors along a boreal secondary forest successional trajectory

Forest succession is an important process regulating the carbon and nitrogen budgets in forest ecosystems. However, little is known about how and extent by which vegetation succession predictably affects soil CO2, CH4, and N2O fluxes, especially in boreal forest. Here, a field study was conducted along a secondary forest succession trajectory from Betula platyphylla forest (early stage), then Betula platyphylla-Larix gmelinii forest (intermediate stage), to Larix gmelinii forest (late stage) to explore the effects of forest succession on soil greenhouse gas fluxes and related soil environmental factors in Northeast China. The results showed significant differences in soil greenhouse gas fluxes during the forest succession. During the study period, the average soil CO2 flux was greatest at mid-successional stage (444.72 mg m-2 h-1), followed by the late (341.81 mg m-2 h-1) and the early-successional (347.12 mg m-2 h-1) stages. The average soil CH4 flux increased significantly during succession, ranging from -0.062 to -0.036 mg m-2 h-1. The average soil N2O flux was measured as 17.95 μg m-2 h-1 at intermediate successional stage, significantly lower than that at late (20.71 μg m-2 h-1) and early-successional (20.85 μg m-2 h-1) stages. During forest succession, soil greenhouse gas fluxes showed significant correlations with soil and environmental factors at both seasonal and successional time scales. The seasonal variations of soil GHG fluxes were mainly influenced by soil temperature and water content. Meanwhile, soil MBN and soil NO3--N content were also important factors for soil N2O fluxes. Structural equation modelling showed that forest succession affected soil CO2 fluxes by changing soil temperature and microbial biomass carbon, affected soil CH4 fluxes mainly by changing soil water content and soil pH value, and affected soil N2O fluxes mainly by changing soil temperature, microbial biomass nitrogen, and soil NO3--N content. Our study suggests that forest succession mainly alters soil nutrient and soil environment/chemical properties affecting soil CO2 and N2O fluxes and soil CH4 fluxes, respectively, in the secondary forest succession process.

Extracellular enzyme stoichiometry reflects the metabolic C-and P-limitations along a grassland succession on the Loess Plateau in China

Soil extracellular enzyme stoichiometry (EES) reflects the biogeochemical balance between microbial metabolic requirements and environmental nutrient availability. Recent research suggests that EES well effect on soil microbial metabolic limitations (SMMLs), however, few field studies have explicitly tested this based on a herbaceous successional chronosequence. We used the EES models to identify the response of SMMLs, and investigated the potential implications of microbial nutritional limitations across the time series (herbaceous succession) and space (transformation interface soil [TIS] and underlying topsoil [UTS] layer) in the grassland restoration series. We show that soil microorganisms were generally limited by C, both in the TIS and UTS. Microbial C-limitation exhibited a unimodal direction, peaking in intermediate successional stages, however, P-limitation presented the opposite trend. During herbaceous succession, microbial P-limitation was more substantial than that in N-limitation. SMMLs gradually transferred from P- to N- and back to P-limitation at later successional stages in the TIS layer. Furthermore, we demonstrate that biotic factors, soil basic index, and soil nutrients explained 92.2 % of the variations in microbial C-limitation and 84.4 % of the variations in microbial P-limitation. Multi–interaction factors exhibited the most significant relative influences of 65.11 % (TIS) and 43 % (UTS) on the SMMLs. Microbial C-limitation was induced by the imbalance between C supply and microbial C demand, whereas the changes in microbial P-limitation were due to the changes in the competition for P between plants and microorganisms. Overall, our findings provide support for microbial C- and P-limitation in the process of herbaceous succession during the restoration. We also highlight the possibility of additive effects on soil SMMLs via interactions of vegetation composition, soil properties, and microbial nutritional demands, which might constrain soil microbial metabolism requirements despite greater living root and litter resource inputs.

Small herbivores and abiotic heterogeneity promote trait variation of a saltmarsh plant in local communities.

Intraspecific trait variation (ITV) enables plants to respond to global changes. However, causes for ITV, especially from biotic components such as herbivory, are not well understood. We explored whether small vertebrate herbivores (hares and geese) impact ITV of a dominant clonal plant (Elytrigia atherica) in local communities. Moreover, we looked at the relative importance of their direct (e.g., selective grazing) and indirect effects (altering genotypic richness/diversity and abiotic environment) on ITV. We used exclosures at two successional stages in a Dutch saltmarsh, where grazing pressure at the early successional stage was ca. 1.5 times higher than that of the intermediate successional stage. We measured key functional traits of E. atherica including height, aboveground biomass, flowering (flower or not), specific leaf area, and leaf dry matter content in local communities (1 m × 1 m plots) inside and outside the exclosures. We determined genotypic richness and diversity of each plant using molecular markers. We further measured abiotic variations in topography and clay thickness (a proxy for soil total nitrogen). Structural equation models revealed that small herbivores significantly promoted ITV in height and flowering at the early successional stage, while they marginally promoted ITV in height at the intermediate successional stage. Moreover, the direct effects of herbivores played a major role in promoting ITV. Small herbivores decreased genotypic diversity at the intermediate successional stage, but genotypic richness and diversity did not impact ITV. Small herbivores did not alter topographic variation and variation in clay thickness, but these variations increased ITV in all traits at the early successional stage. Small herbivores may not only impact trait means in plants as studies have shown but also their ITV.

To what extent does the species composition of Macaronesian laurel forests depend on their human disturbance history and environmental drivers?

Deforestation and forest fragmentation have serious negative consequences for biodiversity and species distribution, but many studies approach species distributions and speciation processes without taking in account the local history of human disturbances. Nevertheless, the complex recovery process after forest destruction is widely distributed around the world and takes place under a wide mosaic of biotic and abiotic factors that may be influencing the species distribution. In this study aerial pictures from 1951 and 2019 were used to assess forest recovery during about sixty years. We tested if the initial stage (forest completely destroyed or young growth forest in 1951) determines the successional process, evaluating the role of different spatial drivers (distance from remnant forest fragments and unfelled areas around each site) and mesoclimate conditions, by examining 40 disturbed sites and 18 old-growth forest sites distinguished in 1951 aerial photos. The final stage during this successional process was assessed using 2019 aerial photos, covering the same these sites. At each plot, plant species composition and forest structure were studied, which allowed us to obtain a maturity index. Our results reveal that the initial stage is not the only driver explaining forest structure and species composition at the end of the 60-year period analyzed. The role of each forest recovery driver varies depending on each stage. In the early successional stages, the slope aspect (exposure) was the most important factor, which is correlated with mesoclimatic conditions, followed by the distance from young-growth forest in 1951. However, in intermediate successional stages the cover of old-growth forest around each plot in 1951 was the main factor in the recovery. At the end of the study period (2019), the differences in species richness between young-growth and old-growth forest were not significant, although old-growth forests were characterized by high densities of endemics, threatened species and β-diversity, showing the species composition a strong dependence on forest structure. Our results reveal the important need to consider human disturbance history in forest research and how climate conditions and the lack of nearby remnants can negatively affect the forest recovery process, greatly increasing the time needed to return to old-growth laurel forest conditions, which requires specific management recommendations.

Respiração basal do solo sob três diferentes coberturas vegetais no Paraná

This study evaluated the soil basal respiration (SBR) of three forest types and seasons and their correlation with pedological attributes in the 0-5 cm land layer. Therefore, we selected two areas of commercial tree species in the central-southern Paraná region: one plot of Pinus taeda and one of Eucalyptus dunnii; and a control, a patch of native forest (Mixed Ombrophyllous Forest). We determined the SBR by the alkaline addition method, incubating the samples for seven days. We collected samples in the cool dry season (winter) and in the hot humid season (summer). Soil attributes were determined by a routine analysis (pH, K+, Ca2+, Mg2+, Al3+, P, Matéria Orgânica, areia grossa e areia fina, silte, argila e V%). We observed significant SBR differences only about summer and winter. SBR correlated significantly with organic matter. These results are similar to most of the literature. There was no difference between the forest types about the SBR, showing that even monoculture forests can present carbon fluxes statistically equal to those of an intermediate successional stage native forest. The specific edaphic fauna adapted to each ecosystem may explain the absence of this difference in relation to SBR.

STRUCTURE AND DIVERSITY OF THE ARBOREAL COMPONENT IN CERRADO SENSU STRICTO IN NORTHERN MINAS GERAIS

Due to a rapid change in the land use in northern Minas Gerais State, southeastern Brazil, large amounts of cerrado have been converted into crops. There is little information about the structure and diversity of the remaining communities in the region. The present study aimed to characterize the structure of the tree vegetation in a cerrado sensu stricto area. We delimited thirty 20m x 20m plots and sampled tree individuals with diameter equal to or greater than 4.8 cm at 30 cm from the ground level (DGH30). We sampled a total of 2616 individuals of 76 species and 33 botanical families. The community showed a density of 2180 ind/ha and a basal area of 17.3 m2/ha. Qualea grandiflora, Terminalia fagifolia, and Dimorphandra mollis showed high importance values. Standing dead individuals stood out in the community. The Shannon diversity index (3.10) and Pielou’s evenness (0.70) indicate that the community is in an intermediate stage of succession in comparison with others. Despite the signs of disturbance, the community still includes species of great social and economic importance for the local population. This community’s floristic and structural patterns can be used to reference extractive management, restoration, and conservation initiatives of other cerrado areas in the region.

Macroecological patterns of the terrestrial vegetation history during the end-Triassic biotic crisis in the central European Basin: A palynological study of the Bonenburg section (NW-Germany) and its supra-regional implications

Abstract The end-Triassic mass extinction is often linked to environmental and climate change triggered by the activity of the Central Atlantic Magmatic Province ca. 201 Mya. In the German Triassic Basin, the transition from pre-extinction to the so-called extinction interval is documented from the fossil-rich Contorta Beds to the mostly barren Triletes Beds. However, despite the lack of macrofossils, plant microfossils are present and studying palynomorph diversity and assemblages still give us a detailed insight into the impact of environmental changes on the flora. Here, we present data from 64 samples taken from the new Triassic-Jurassic section ‘Bonenburgʼ, which originates from a brick quarry in North Rhine-Westphalia (Germany), and encompasses the Triassic–Jurassic transition in the Germanic Basin. Using palynofacies analysis, we document changes in the depositional environment. Based on terrestrial and marine palynological analysis, we also document quantitative changes in four assemblage zones for correlation with other European sections. Further, we discuss the vegetation history with special focus on the transition from the pre-extinction to extinction interval (Contorta to Triletes Beds). Additionally, we investigate palynofloral diversity patterns especially prior to the Triassic-Jurassic transition, to evaluate the ecological impact of environmental upheaval on the flora. Furthermore, we document intraspecific palynomorph variability, indicating a variety of aberrant spore, pollen, and tetrad formation, in the middle Rhaetian, the lowermost upper Rhaetian, and the lowest Hettangian. Our study supports existing paleogeographical reconstructions for the region and reveals, that vegetation underwent gradual changes with intermediate successional stages rather than dramatic extinction or drastic turnover as documented for animals. Diversity patterns coinciding with aberrant palynomorph occurrences, potentially associated with episodes of increased environmental stress, suggest three disturbances pulses of probably increasing severity. Although environmental stress in the context of diversity patterns seems a likely explanation for the occurrence of aberrant palynomorphs, further investigations are needed to better understand the underlying mechanisms and their evolutionary significance and temporal connection with biotic crises.

Seed biometry: another functional trait in caatinga

Seed biometrics is an excellent tool for understanding environmental filters, species potential and dispersal, successional stages of communities and the dynamics used by seeds to germinate, establish and develop, thus constituting a functional trait of the species. We aim to understand the relationship between aspects of seed biometrics and other phenological traits, in order to infer contributions about functional strategies in Caatinga. Between September 2017 and January 2019, 10 individuals of Cenostigma pyramidale (Tul.) LP Queiroz, Commiphora lepthophloeos (Mart.) JB Gillett, Jatropha mollissima (Pohl.) Baill., Monteverdia rigida (Mart.) Biral. Pseudobombax marginatum (A.ST.-Hil) A. Robyns, Zizyphus joazeiro Mart. were monitored for the selection of three seed collection matrices. From each matrix 100 seeds were collected, which after screening resulted in 35 intact seeds that were used to measure length, width, thickness and volume. Caatinga seeds are generally small, as a result of the environmental stresses of the Brazilian semiarid. The analyzed variables separated three groups in the PCA. We noticed that these groups evidenced the successional stages in the Caatinga. One group included M. rigida and P. marginatum, which are late secondary. C. pyramidale and C. lepthophloeos formed another group coincident with intermediate successional stages. J. mollissima and Z. joazeiro formed a group of pioneer species in anthropized environments. Another finding was that the area was in secondary succession. The pioneer species presented the largest seeds and this characteristic is associated with the need for nutrient reserve that allows the embryo to germinate and last for a longer period without the need for exogenous nutrients, an essential condition for the Caatinga. With the advancement of ecological succession and the establishment of a more consolidated plant community, competition for resources, the frequent dispersion vector type and the nature of the environmental stresses present, the seeds may be smaller.

Development of Nutrient Uptake by Understory Plant Arrhenatherum elatius and Microbial Biomass during Primary Succession of Forest Soils in Post-Mining Land

The development of plant and soil microbial communities is one of the basic preconditions for the restoration of functional ecosystems. However, nutrients are concurrently used by plants and microbes, and the dynamics of this interaction during ecosystem development have seldom been studied. The aim of our study, thus, was to describe the dynamics of nutrient availability in soil and, at the same time, the nutrient accumulation in plant and microbial biomass along an unassisted primary succession heading toward broadleaf forest. The growth of the understory plant Arrhenatherum elatius on soils originating from three (16, 22, and 45 years’ old) successional stages of a post-mining area and the development of the microbial community in the presence or absence of this plant were studied in a pot experiment. Both, the plant biomass and carbon (C) in microbial biomass in intermediate and late middle successional stages were higher than those in the early stage. In soil, extractable organic C, extractable organic nitrogen (N), and inorganic N increased with proceeding succession, but Olsen phosphorus (P) peaked in the intermediate successional stage. The amounts of N and P in plant and microbial biomass increased during succession. In the late middle successional stage, the amount of P in microbial biomass exceeded that of plant bound P approximately twice, and this increase was higher in pots with plants than without. The results imply that the competition between plants and microbes for available P may increase microbial P uptake and, thus, hinder plant growth in later successional stages.

Modeling tree diversity, stand structure and productivity of northern temperate coniferous forests of Mexico.

There is increasing evidence complex forest structure and tree diversity correlates positively with the productivity of forest ecosystems. However, there is little quantitative information regarding the effect of these factors on stand productivity of northern temperate coniferous forests of Mexico. This study aimed to test the hypothesis tree diversity and canopy structure positively associates with forest productivity. Parameterization of tree diversity, stand structure and productivity were carried out on dasometric data from 36 permanent sampling plots re-measured in 1982, 1993, and 2004. Statistical analysis of stand parameters tested the null hypothesis. Statistical relationships revealed well-balanced canopy strata and imbalanced diameter structures positively correlated with stand productivity. Tree diversity was also positively linked with stand productivity, but the effect appeared to be most important in the early to intermediate stages of succession. Further research is required to understand the long-term effects of tree diversity and canopy structure on stand productivity. These preliminary observations stress the importance of prescribing silvicultural practices that maintain the three-dimensional structure of stands and diversity of forest canopies that aim to preserve ecosystem function, diversity, and productivity.

The effect of arbuscular mycorrhizal fungi Rhizophagus intraradices and soil microbial community on a model plant community in a post-mining soil

The aim of this study was to assess the effect of arbuscular mycorrhizal fungi Rhizophagus intraradices and soil microbial groups and their interactions on a simple plant community in a microcosm experiment. The experiment was performed with two grass species (Poa compressa, Festuca rubra) and two herb species (Centaurea jacea, Lotus corniculatus) which are characteristic of intermediate succession stages in post-mining sites. Three months before the start of the experiment, bacteria, saprophytic fungi, protists, and their combined treatments were inoculated into the soil. At the start of the experiment, half of the pots were inoculated with mycorrhiza. After 60 days, plants were harvested and shoot and root biomass and microbial respiration and biomass were assessed. Above- and belowground plant biomass was significantly lower in the treatments with mycorrhiza. The effect was significant for aboveground biomass of grasses, especially that of Poa compressa, and for grass/herb ratio but not for herbs. Microbial respiration was also lower with mycorrhiza. Among microbial community treatments, saprophytic fungi showed significant effects on plant growth. The results showed the importance of mycorrhizal fungi on plant biomass and its interaction with different plant species and microbial groups which would be useful when extrapolating these results to a natural environment.

Succession matters: Community shifts in moths over three decades increases multifunctionality in intermediate successional stages

Species composition strongly depends on time, place and resources. In this context, semi-natural grasslands belong to the most species-rich habitats of Europe, and succession may eventually cause local extinction of typical grassland species, but conversely increase species richness due to habitat diversification. Here, we analyse potential effects of succession of calcareous grasslands on moths. Our studied community, assessed over three decades in south-eastern Germany, comprised >1000 species. We compiled data on the ecology of each of these species, considering the larval and adult stages. We assigned Ellenberg indicator values to each main larval food plant species used by these lepidopterans. Changes in the community means of these indicators were applied to test for possible consequences of the changes in habitat structure and quality. Our data revealed increasing multifunctionality of community structure, higher variability of habitat association over time, the appearance of range expanding species, but also local extinction of various typical grassland moth species. These shifts in species composition mirror effects of succession, which frequently transform previously homogenous semi-natural grasslands into a heterogeneous habitat mosaic.

Carabid beetle (Coleoptera: Carabidae) assemblages in the intermediate successional stage after Mt. Bandai eruption of 1888: Effects of environmental variables on carabid beetles in the Urabandai area

AbstractWe studied carabid beetle assemblage structure and species diversity in an intermediate successional stage (seral) forest established in areas affected by the 1888 eruption of Mt. Bandai and a climax forest that had not been affected by the eruption at the Urabandai area, Fukushima Prefecture, Japan. In total, 2,131 carabid beetles representing 31 species were collected using pitfall traps without bait. A comparison of carabid beetle assemblages between the two forest types revealed that the number of species observed was comparable, but their abundance was greater in the seral forest. The assemblage structure clearly differed between the two forest types. In the seral forest, forest generalists, such as Synuchus arcuaticollis and Pterostichus prolongatus, along with forest specialists including Carabus vanvolxemi and Pterostichus asymmetricus, were collected. In the climax forest, forest generalists, such as Synuchus cycloderus and Carabus albrechti tsukubanus, were more abundant than forest specialists. This suggests that the current seral forest in the Urabandai area possesses environmental variables that enable the coexistence of both forest specialist and generalist beetle species. A redundancy analysis showed that six species from the genera Synuchus and Pterostichus were associated with high canopy openness and high understory vegetation cover, whereas species recorded only in the climax forest were associated with deep litter. Therefore, it seems likely that carabid beetles in the Urabandai area were affected by these three environmental variables.

Synergistic Succession of the Small Mammal Community and Herbaceous Vegetation after Reconverting Farmland to Seasonally Flooded Wetlands in the Dongting Lake Region, China

We investigated the synergistic succession of the small mammal and herbaceous communities after farmland was reconverted to seasonally flooded wetlands in the Dongting Lake Region of China. The composition of small mammals and the herbaceous community was examined in four habitat types: F (farmland), S (where agriculture continued, but human habitation ceased), R (farmland reconverted back to seasonally flooded wetlands), and B (aboriginal seasonally flooded wetlands). Using various diversity indices, the data showed that the small mammal community changed in parallel with the succession of the herbaceous community. Compared to F, there was little change in S, whereas R noticeably changed. Microtus fortis inhabited R, because Carex spp. was the dominant plant species. R held a mixture dominant species from both F and B, demonstrating that R was in transition (intermediate stages of succession) from F to B. However, the status of the small mammal community in B changed in 2008–2010, due to the operation of the Three-Gorge Reservoir (TGR). In conclusion, our observations demonstrate that the succession of the small mammal community in habitats R and B are directly influenced by human activity in the region, with monitoring being required to continue documenting these changes.