Microhabitat Variables Research Articles

Functional and phylogenetic analyses of tadpole community assembly in temperate montane streams

Understanding the spatial patterns and the maintenance of biodiversity is a central target in ecology and biogeography, which provide important insights into community assembly processes. Mountain ecosystems provide informative systems for examining how biodiversity is distributed and identifying the mechanisms underlying those patterns. However, most of the existed studies only focused on plants, birds, and microbes, while little attention has been paid on amphibians, especially tadpoles. In the present study, we explored the elevational patterns of multiple facets of tadpole diversity and the community assembly mechanisms in temperate montane streams of Mount Emei, China. The taxonomic, functional, and phylogenetic diversity of tadpole assemblages in montane streams were quantified. Their elevational patterns were investigated using first and second-order polynomial regression analyses. The microhabitat determinants of these patterns were assessed by ordinary least squares models and hierarchical partitioning analyses. The phylogenetic tree of tadpoles and the Eucliden distance of traits between tadpoles were constructed. They were subsequently used to calculate the standardized effect size of mean pairwise phylogenetic and functional distances, and to speculate the tadpole assembly rules. Our results indicated that the Faith’s PD and the standardized effect size of Faith’s PD had hump-shaped responses to elevation, while the relationships between elevation and observed taxonomic diversity, observed functional diversity, and the standardized effect size of functional diversity were not significant. Interestingly, these patterns were determined by microhabitat variables, such as water conductivity, river width, water depth, and substrate type. Mean pairwise phylogenetic distance also showed hump-shaped correlations with the elevational gradient. Tadpole functional and phylogenetic structures were more clustered in low and high elevational streams, suggesting that environmental filtering was the main driver. At mid-elevations, functional and phylogenetic structures were overdispersal, indicating that limiting similarity plays a dominant role in shaping the tadpole assemblages.

Geology, climate, and hydrochemistry shape the spatial patterns of multiple diversity facets and functional traits of fishes

AbstractIn a large river with significant environmental variations in space (i.e., microhabitat) or over time (i.e., seasonality and/or long‐term trend), discovering the spatial changes in fish diversity, distributions, and functional traits would provide an important foundation for the understanding of ecosystem structure and function. In the Pearl River in China, three datasets as fish distribution, species functional traits, and environmental variables were constructed and sorted to (1) test the relationships between and congruence of taxonomic diversity, functional diversity, and phylogenetic diversity by a randomisation procedure, (2) map the spatial pattern of diversity and the correlation to environmental variables by maximal information coefficient, and (3) determine the fish traits tendency under environmental changes by the fourth‐corner method. The Pearl River possesses the highest fish richness among all the rivers in China, with 438 freshwater fish species including 119 cave species. At basin scale, phylogenetic diversity showed faster change than functional diversity, suggesting a little divergence of functional traits despite high phenotypic or genetic diversity across species, as parallel evolution. However, at a small scale, when only considering cave fishes, the variation rate of species traits was faster than that of species increase, as evolutionary radiation in a variety of microhabitats. For all three aspects of diversity, random permutation tests confirmed that congruence values in each grid cell were significantly different from the random expectations. Besides widely accepted variables such as altitude, precipitation, and slope concerned with fish biogeography, hydrochemical variables showed influential impacts on the morphological and growth traits of fishes in the Pearl River characterised by the dominance of the karst habitat.

Karst Dolines Support Highly Diversified Soil Collembola Communities—Possible Refugia in a Warming Climate?

Karst dolines, as geomorphologically diverse natural landforms, usually exhibit more or less steep microclimatic gradients that provide a mosaic of diverse microhabitat conditions, resulting in a high diversity of soil biota with numerous rare endemic and/or relict species occupying these habitats. In this study, we investigated the spatial patterns of Collembola abundance, species richness, community structure and distribution of functional groups at topographically and microclimatically different sites across three open (unforested) karst dolines in a north-south direction in the Slovak Karst, Slovakia. We also assessed the refugial capacity of dolines for collembolan communities. The Friedman ANOVA test confirmed the significant differences in soil mean temperatures between the sites of all the dolines selected. The diverse soil microclimatic conditions within the dolines supported higher Collembola diversity (species numbers, diversity indices) compared with sites on the karst plateau and showed a potential to facilitate the persistence of some species that are absent or very rare in the surrounding landscape. In dolines with circular morphology and comparable size, the topography and soil microclimate had a stronger effect on community composition and structure than soil organic carbon. Shallow solution dolines provided microhabitats for various functional groups of soil Collembola in relation to the microclimatic character of the individual sites. It was observed that such landforms can also function as microclimatic refugia for cold-adapted species through the accumulation of colder air and the buffering of the local microclimate against the ambient mesoclimate, thus underlying the necessity of adequate attention in terms of the conservation of the karst natural phenomena.

Multi-spatial analysis on cave ecosystems to predict the diversity of subterranean invertebrates

Subterranean habitats around the world can shelter diversified and threatened faunal communities. However, issues related to alterations in the landscape and structure of subterranean habitats still need to be better understood. Therefore, we used a multi-spatial scale analysis of land cover, land use, and cave habitats to predict the diversity of communities of subterranean invertebrates. We hypothesized that changes in land cover promote alterations in both faunal richness and composition and microhabitat diversity and that microhabitat features determined subterranean biodiversity. Sixteen limestone caves were sampled in Brazil at micro, meso, and macro scales using quadrats (1m²), transects (100 meters) as sample units inside caves and buffers with the radius of 100 and 250 meters in the surroundings of the cave entrances. Models performed showed that land cover and land use influenced cave environments, regarding both microhabitats traits and terrestrial invertebrate richness and composition. We also observed a relationship between microhabitat structure and terrestrial invertebrate richness and composition. Our results showed that deforested areas had negative effects on species richness and changed their composition, while natural areas had positive effects on microhabitat diversity. The same effects were observed for both 100 and 250 meters buffers. Invertebrate richness was negatively predicted by deforested areas while positively predicted by natural areas. Richness was also positively predicted by the combination of all microhabitat traits, and dissimilarity of fauna was influenced by microhabitat diversity in mesoscale and microscale by all microhabitat elements. The results highlight the importance of the landscape surrounding the caves to conserve the subterranean habitats and their fauna. Due to the spatial and temporal changes in the global environmental scenario, we argue the urgency of further detailed studies in fragmented landscapes to define minimum areas of protection for cave environments.

Differentiation and seasonality in suitable microsites of seed dispersal by an assemblage of omnivorous mammals

In endozoochorous seed dispersal, the ecological characteristics of each disperser determine the quantitative and qualitative aspects of the dispersal mechanism. To understand the role of different frugivores in multispecies seed dispersal networks, it is necessary to focus on the community structure and investigate where in the landscape seed deposition occurs. The aim of this research was to assess the quantitative and qualitative aspects of a mammalian endozoochorous seed dispersal network in a temperate forest ecosystem and identify the seasonal dispersal niche of each member of the assemblage. We hypothesized that differences among dispersers and seasons would occur in (H1) the proportion of scats that contain seeds, seed abundance in scats, and the number of seed species dispersed per scat, and in (H2) the probability of dispersing seeds to suitable microsites for germination of each species and seed abundance. We also hypothesized (H3) that the microhabitat variables of deposition sites would vary among dispersers, and (H4) that complementary structures would occur in terms of dispersers, dispersed species, and deposition sites. From summer (June–August) to autumn (September–November) in 2003 and 2004, we collected scats of five mammalian frugivorous species and recorded eight microhabitat variables at each deposition site in central Japan. We recorded the presence and number of seeds in scats and identified all seed at the species level. We considered a deposition site as suitable when the habitat type (interior forest, treefall gap, forest edge, and outside the forest) at a deposition site matched the microhabitat required for the for the dispersed species to germinate and survive as seedlings. A total of 341 scats containing seeds of 16 fleshy-fruited species were collected. Among these, 213 (62.5 %) scats were dispersed to suitable habitats (summer: 68.8 %, autumn: 54.8 %). We found that the seed abundance in the scat varied among dispersers and was higher in autumn (H1–2). The probability of dispersing seeds to suitable microsites switched among dispersers from summer to autumn (H2). The distinctive microhabitat variables and variation in microhabitat at deposition sites differed among dispersers across seasons (H3). Disperser-plant and disperser-deposition site networks were specialized and modular in structure compared to random networks during both seasons, but there was a less nested structure in summer compared to autumn (H4). The five mammal species showed differences and seasonality in seed dispersal niches. Because of these differences, these mammal species may play redundant and complementary roles in the seed dispersal network.

Habitat associations of riverine fishes among rocky shoals

AbstractUnderstanding species' associations with physical habitat conditions is a fundamental goal of ecology. For organisms that occupy lotic ecosystems, relationships to streamflow are of particular importance, but these associations are unstudied for most species. We tested the predictability of fish–microhabitat relationships in river shoals (shallow, rocky areas with relatively swift water flow) using a large data set from the Conasauga River in Georgia, USA. Our objective was to assess the consistency of species‐specific relationships with flow‐dependent variables (depth, velocity, Reynolds number and Froude number) while accounting for other microhabitat variables (e.g. vegetation). We used data from 8285 seine‐sets collected during late summer or autumn at 26 sites over 12 years to relate occurrence and counts of 22 fish species to habitat variables using generalised linear multiple regression models. Results showed that microhabitat models explained a substantial amount of the variation in counts for some species, although other species were poorly predicted. We classified 16 species as velocity specialists and nine species as depth specialists, with six species specialised for depth and velocity and three species classified as depth and velocity generalists. The variability in habitat associations that we observed suggests that species will be unevenly affected by anthropogenic activities that alter flows.

Effect of environmental and microhabitat variables on tardigrade communities in a medium-sized city in central Argentina

Effect of environmental and microhabitat variables on tardigrade communities in a medium-sized city in central Argentina

High polychaete diversity in the Gulf of Guinea (West African continental margin): The influence of local and intermediate scale ecological factors on a background of regional patterns

The Tropical East Atlantic is one of the least studied areas in the world's oceans, and thus a blank spot on the map of marine studies. Shaped by dynamic currents and shifting water masses, it is a key region in discussions about marine ecology, biodiversity, and zoogeography, while facing numerous, poorly understood, and unmonitored threats associated with climate change, acidification, and pollution. Polychaete diversity was assessed along four transects along the Ghana coast, from shallow to deep bottoms and distributed along the whole upwelling marine ecoregion. Despite high sampling effort, steep species accumulation curves demonstrated the necessity of further sampling in the region. We observed zonation of fauna by depth, and a decrease in species richness from 25 m to 1000 m depth. Polychaete communities were influenced by sediment type, presence of oxygen minimum zones, and local disturbances caused by elevated barium concentrations. Similar evenness along the depth gradient reflected the importance of rare species in the community structure. Differences in phylogenetic diversity, as reflected by taxonomic distinctness, were small, which suggested high ecosystem stability. The highly variable species richness at small scale (meters) showed the importance of ecological factors giving rise to microhabitat diversity, although we also noticed intermediate scale (50–300 km) differences affecting community structure. About 44 % of the species were rare (i.e. recorded only in three or fewer samples), highlighting the level of patchiness, while one fifth was distributed on all transects, therefore along the whole upwelling ecoregion, demonstrating the influence of the regional species pool on local communities at particular stations. Our study yielded 253 species, increasing the number of polychaetes known from this region by at least 50 %. This casts doubt on previous findings regarding Atlantic bioregionalization, biodiversity estimates and endemism, which appear to have been more pronouncedly affected by sampling bias than previously thought.

Climate change may cause the extinction of the butterfly Lasiommata petropolitana in the Apennines

Climate change represents a threat to narrow-ranged mountain species living in low-altitude massifs. We studied the disjunct Apennine population of Lasiommata petropolitana (Lepidoptera, Nymphalidae) in the Gran Sasso and Monti della Laga National Park. We quantified the altitudinal shifts undergone in the last decades (1964–2021) in the Alps and Apennines and estimated the local extinction risk due to climate change. We also sequenced the COI mitochondrial marker of seven Apennine specimens, comparing them with those available across the Palearctic. We projected the probability of presence for the species under a future climatic scenario using an ensemble forecasting approach. We found that, despite geographical isolation, the Apennine population of L. petropolitana displays a single widespread COI haplotype also occurring in most European populations. In the Alps and Apennines, this species has shifted uphill an average of 6.3 m per year since 1964. Accordingly, our model predicted a likely extinction in the Apennines by about 2060, due to a reduction of the climatic suitability in this region.Implications for insect conservationImplications for insect conservation Despite its potential loss in the Apennines would not erode mitochondrial diversity, L. petropolitana characterises the butterfly community of the Gran Sasso massif as an alpine enclave. The loss of the Apennine population, together with those of other orophilous butterflies, could trigger a homogenization of alpha and beta diversity and induce a loss of functional diversity in the impoverished high-altitude biotas. As habitat heterogeneity is a key aspect for populations to endure climate change, the maintenance of varied microhabitats, mainly through grazing management, could address the decline of this population.

Fractal analysis of seahorses in Mindanao, Philippines: A tale of their own

Abstract. Tabugo SR, Claver PSS. 2022. Fractal analysis of seahorses in Mindanao, Philippines: A tale of their own. Biodiversitas 23: 5233-5238. Monitoring populations of species is essential for science-driven policymaking. However, monitoring can be a daunting task for threatened and vulnerable species like seahorses. They are often threatened by overfishing and habitat destruction in the marine environment. Since they are considered a flagship species, monitoring populations in Panguil and Murcielagos Bay, which served as the home of the two common seahorses in Mindanao, Philippines, is vital. Fractals naturally occur in nature and hence can be used as possible predictors. Morphometric complexity patterns were investigated in the Hippocampus kuda and Hippocampus comes via fractal geometry to delineate irregular non-euclidean objects. The difference between fractal dimension and lacunarity values was tested between species. The hypothesis states that high fractal dimensions are deviations from the equilibrium state/chaos and, thereby, can be linked to vulnerability. High mean fractal dimension (Da) based on box-counting and coefficient of variation (CV) of the lacunarity method were found in H. kuda (F) and H. comes (F). The observed variations can be attributed to morphological complexity as they have adapted to varied microhabitats. Herewith, fractals can be a fast, easy, convenient, and non-invasive way of monitoring species. The results of the study can support conservation protection measures for the two species.

Fractal analysis of seahorses in Mindanao, Philippines: A tale of their own

Abstract. Tabugo SR, Claver PSS. 2022. Fractal analysis of seahorses in Mindanao, Philippines: A tale of their own. Biodiversitas 23: 5233-5238. Monitoring populations of species is essential for science-driven policymaking. However, monitoring can be a daunting task for threatened and vulnerable species like seahorses. They are often threatened by overfishing and habitat destruction in the marine environment. Since they are considered a flagship species, monitoring populations in Panguil and Murcielagos Bay, which served as the home of the two common seahorses in Mindanao, Philippines, is vital. Fractals naturally occur in nature and hence can be used as possible predictors. Morphometric complexity patterns were investigated in the Hippocampus kuda and Hippocampus comes via fractal geometry to delineate irregular non-euclidean objects. The difference between fractal dimension and lacunarity values was tested between species. The hypothesis states that high fractal dimensions are deviations from the equilibrium state/chaos and, thereby, can be linked to vulnerability. High mean fractal dimension (Da) based on box-counting and coefficient of variation (CV) of the lacunarity method were found in H. kuda (F) and H. comes (F). The observed variations can be attributed to morphological complexity as they have adapted to varied microhabitats. Herewith, fractals can be a fast, easy, convenient, and non-invasive way of monitoring species. The results of the study can support conservation protection measures for the two species.

: On growth patterns and mechanisms in arctic-alpine shrubs

Arctic-alpine ecosystems are considered hot-spots of environmental change, with rapidly warming conditions causing massive alterations in vegetational structure. These changes and their environmental controls are highly complex and variable across spatial and temporal scales. Yet, despite their numerous implications for the global climate system, the underlying physiological processes and mechanisms at the individual plant scale are still little explored. Using hourly recordings of shrub stem diameter change provided by dendrometers, paired with on-site environmental conditions, enabled us to shed light on these processes. In this way, growth patterns in three widely distributed shrub species were assessed and linked to thermal and hygric conditions. We started our analysis with a close examination of one evergreen species under extreme environmental conditions, followed by a comparison of evergreen and deciduous species, and, finally, a comparative look at growth patterns across local micro-habitats. The results revealed distinct growth strategies, closely linked to species-specific water-use dynamics and cambial rhythms. Within the heterogenous alpine landscape these conditions were mainly attributed to the variation in local micro-habitats, defined by fine-scale topography and consequent variation in snow conditions and exposure. Thus, the overall growth success was mainly controlled by complex seasonal dynamics of soil moisture availability, snow conditions, and associated freeze–thaw cycles. It was therefore in many cases decoupled from governing regional climate signals. At the same time, exceedingly high summer temperatures were limiting shrub growth during the main growing season, resulting in more or less pronounced bimodal growth patterns, indicating potential growth limitation with on-going summer warming. While shrubs are currently able to maximize their growth success through a high level of adaptation to local micro-site conditions, their continued growth under rapidly changing environmental conditions is uncertain. However, our results suggest a high level of heterogeneity across spatial and temporal scales. Thus, broad-scale vegetational shifts can not be explained by a singular driver or uniform response pattern. Instead, fine-scale physiological processes and on-site near-ground environmental conditions have to be incorporated into our understanding of these changes.

Potential effects of Cladophora oligoclora Decomposition: Microhabitat variation and Microcystis aeruginosa growth response

Excessive proliferation of filamentous green algae (FGA) is a new ecological problem in lake systems that have not yet reached a steady state. However, knowledge on how FGA decomposition affects the physical and chemical properties of microhabitats, and whether FGA decomposition stimulates the growth of harmful microalgae in the same niche and promotes the formation of harmful algal blooms remains unclear. In this study, we investigated the decomposing effect of a typical FGA, Cladophora oligoclora, on the density and photosynthetic capacity of Microcystis aeruginosa. C. oligoclora decomposition was characterized under different conditions, namely, unshaded and aerobic, unshaded and anoxic, shaded and anaerobic, and shaded and anoxic, which represented different environmental states in the sedimentation process of decaying C. oligoclora mats from water surface to sediment. The shaded and anaerobic treatment significantly decreased the dissolved oxygen and pH of the culture medium by 66.48 % and 7.21 %, respectively, whereas the conductivity and total organic carbon increased by 71.17 and 70.19 times compared with the control group, respectively. This indicated that the decomposing C. oligoclora deposited at the bottom under dark and anaerobic conditions in natural waters had the greatest impact on the lake environment. Further, the cell density of M. aeruginosa was higher than that in the control group with low concentration (10 % of decomposing solution), whereas the cell density and photosynthetic activity decreased significantly at high concentration of the decomposing solution. Fatty acids and phenolic acids were identified as the main Cyanobacteria-inhibiting active substances in the organic acid components of the decomposing solution. Furthermore, phenol, 4-methyl- and indole compounds were active organic lipophilic compounds in the residue and solution of decomposing C. oligoclora were difficult to degrade. Our findings will be valuable for understanding the succession relationships between FGA and cyanobacteria, which have the same niche in lake ecosystems.

Scale‐dependence of fish habitat associations in a North American river system

Abstract Determining the appropriate measurement scale to assess habitat variables is critical for ecologists assessing biological or ecological conditions. Depth, velocity, substrate, woody debris and other fish cover variables occur on both reach and microhabitat scales, and fish habitat associations with these variables may be scale‐dependent. The aim of this work was to better understand the importance of scale for fish–habitat associations with these variables in a framework consistent with environmental filtering and to test the hypothesis that habitat variable importance is scale‐dependent. I used prepositioned areal electrofishing in wadeable streams of the Delaware River basin to evaluate the associations of fish with the same variables summarised on different reach and microhabitat scales. The importance of scale for fish–habitat associations was assessed using two approaches that approximate an environmental filtering framework: variance partitioning with (1) ordination and (2) generalised linear mixed models. Variables on both the reach and microhabitat scales explained a significant fraction of the total variation in fish community composition (p < 0.05). Variation decomposition of reach‐ and microhabitat‐scale effects revealed 20.2% and 2.0% of all variation were due uniquely to reach and microhabitat scales, respectively. Measures of coarseness, embeddedness, amount of riffle and areal coverage of five fish cover variables were significant explanatory variables of community composition at the reach scale only (p < 0.05). Velocity and mesohabitat (amount or presence of riffle) were the only two habitat features that were significant explanatory variables of fish community composition at both the reach and microhabitat scales (p < 0.05). Individual models of species occurrence revealed similar patterns as seen with analyses of community composition. For many fishes, habitat features quantified at the reach scale were more explanatory than at the microhabitat scale. Longnose dace (Rhinichthys cataractae) were more dependent upon microhabitat variables than reach‐scale variables, relative to other fishes. Mean velocity at the reach scale was the most important explanatory variable for explaining fish community composition and indicated support for the concept of environmental filtering at the reach and microhabitat scales. Few studies of fish occurrence have incorporated a study design and analytical framework that approximates the hierarchical nature of habitat. This study identifies important scales and predictors, demonstrates the importance of a multiscale approach, and provides support for the environmental filtering concept at the reach and microhabitat scales. These findings will allow ecologists to better account for scale‐dependent habitat associations and justify the use of fish habitat associations on reach and microhabitat scales for assessing biotic integrity, restoration and conservation of fishes.

Microhabitat variables influencing the presence and abundance of birds in floodplain grassland of the lower Ganges and Brahmaputra rivers, Bangladesh

Grassland bird communities are likely declining in all major grassland ecosystems globally due to habitat loss and modification, yet knowledge of the status of many tropical grassland bird communities is relatively poor. This study investigated the bird community structure and its associations with vegetation characteristics and potential human impacts in seasonal floodplain grassland along the lower Ganges and Brahmaputra Rivers, Bangladesh (part of the Indo-Gangetic Plain) during 2018–2019 through point counts of birds combined with vegetation surveys. Bird responses were assessed by diversity indexes, non-metric multidimensional scaling ordination and linear models. Results show that the total resident bird community (31 grassland specialists, 34 generalists and 10 waterbirds) overlapped among the four major vegetation types in the study area (forbs and bushes, Saccharum sp., Cynodon sp. and cropland). The diversity of the total bird community increased with cover of forbs and bushes, while the overall diversity of grassland specialists (those adapted to and reliant on some variety of grassland habitat for part or all of their life cycle whether feeding or breeding.) increased with Saccharum sp. cover but decreased with increased crop cover. The diversity of the total bird community and all grassland specialist birds showed no variation with vegetation height. However, the abundance of grassland specialists showed a strong increase with increases in vegetation height. Among the grassland specialists, nine species that were entirely dependent on tall grasses for breeding were considered as obligate tall grass breeders. The abundance of these tall grass breeders decreased with greater cover of both Cynodon sp. and crops but increased with greater cover of Saccharum sp. The retention of vegetation with heights > 150 cm was therefore important to conservation and management of this community. Regular seasonal herding of cattle in these floodplain grasslands was widespread and it was therefore difficult to compare grazed with ungrazed areas. The diversity of neither the total bird community nor the overall grassland specialists showed any association with grazing intensity. However, grazing impacted negatively on the abundance of obligate tall grass breeders. Limited grass harvesting increased the overall diversity of the grassland specialist bird community. The estimated density of nine species of obligate tall grass breeders ranged from 0.19 to 4.41 birds/ha. Continuing rapid agricultural expansion was observed and is a prominent threat to these birds. More habitat-specific information and monitoring are required to quantify risks and aid conservation planning.

Tree mixtures mediate negative effects of introduced tree species on bird taxonomic and functional diversity

Abstract Recent biodiversity loss has emphasized the necessity to critically evaluate the consequences of human alterations of forest ecosystems. Stand diversification via tree species mixtures and the use of non‐native trees are two such alterations currently gaining importance as climate change adaptations. However, the effects of local versus regional tree mixing on associated biodiversity and notably the modifying role of tree species growing outside their natural range remain poorly understood. We assessed how monocultures and mixtures of native and introduced tree species influence the taxonomic and functional diversity of bird communities at stand and landscape scales in north‐west Germany. We focused on the dominant natural tree species (Fagus sylvatica) and economically important conifer species planted outside their natural range (the native Picea abies and non‐native Pseudotsuga menziesii). We found that bird species richness and functional diversity were generally higher in pure and mixed stands of native F. sylvatica than in pure conifer stands, especially in comparison to non‐native P. menziesii. These differences were particularly strong at the landscape scale. Pure conifer stands harboured only a reduced set of functionally similar bird species. Structural diversity based on tree microhabitat availability emerged as a key predictor of bird diversity. Synthesis and applications. Our study suggests that tree species mixtures do not necessarily increase bird diversity compared to pure stands of native trees, but can promote bird diversity relative to pure stands of species planted outside their natural range. Moreover, local mixtures, rather than a mosaic of pure stands, may promote bird diversity also at the landscape scale. By contrast, pure stands of tree species planted outside their natural range can increase biotic homogenization of forest birds. Promoting structural diversity of microhabitats via tree retention and ensuring that non‐native trees are planted in mixtures with native trees may alleviate potential limitations of climate change‐oriented management for biodiversity.

Diversity and distribution patterns of micromammifers in southern Santa Fe province, Argentina

Species diversity is a central issue in both community ecology and conservation biology and diet analysis of Tyto furcata has proven to be a tool of high methodological value in determining the presence and distribution of micromammals. The objective of this work is to present the diversity, composition and relative abundance of the species that conform the assembly of micromammals in four environments in the south of Santa Fe province, Argentina. It was obtained a total of 8132 prey recovered from 3442 pellets. From the results obtained, it was possible to establish a specific richness (S) for the study area of 20 species of micromammals, among them four species of sigmodontine rodents not documented for the study area: Oligoryzomys nigripes, Calomys venustus, Holochilus chacarius and Graomys chacoensis. This work shows that although the ansembly of micromammals is typical of the Pampean ecoregion, the most complex (vertical variation) and heterogeneous (horizontal variation) environments that are still preserved present species diversity, since they contain greater diversity of microhabitats.

Species-Level Versus Community-Level Responses to Microhabitat Type and Diversity in an Experimental Plant Community

Soil heterogeneity has been theoretically predicted to promote plant performance, but empirical evidence is often mixed. By focusing on a gradient of microhabitats (single, three and six types of microhabitats), we tested the hypothesis that increasing the number of microhabitats promotes the diversity and productivity of plant communities. We created different types of microhabitats by adding different forms of nitrogen (NH4+, NO3− and glycine) or combinations of these nitrogen in an even or patchy way. Community biomass, but not evenness, differed in different types of single-microhabitat. Increasing the number of microhabitat types did not alter community growth or evenness, but it increased the difference in the relative abundance of plant species within the community. These results suggest that microhabitat diversity can influence plant competitive hierarchies, and that this effect can lead to changed community growth, but may not be decisive for plant evenness.

Monetary evaluation of supporting ecosystem services as a habitat provider for birds in Thailand urban park

Abstract. Yarnvudhi A, Leksungnoen N, Siri S, Ponpithuk Y, Sukmasuang R, Duengkae P, Pongcharoen C, Sutummawong N, Marod D, Wachrinrat C, Premashthira A, Tor-ngern P, Poungcharean S, Hermuk S, Kachina P. 2022. Monetary evaluation of supporting ecosystem services as a habitat provider for birds in Thailand urban park. Biodiversitas 23: 4747-4758. Supporting services are important services to maintain ecosystems by providing habitats for organisms and genetic diversity. In this study, the monetary value of supporting services for bird habitats in urban parks was evaluated based on the price for nursing each bird species and market value. Bird diversity was conducted using point count observation. We found total of 53 bird species, 27 families and 8 orders in the park. Total monetary benefit for bird habitats in this park was estimated to be around USD60,354.12 per individual bird with an average value of USD1,138.76 per bird per species. The top three species with the highest monetary value were the Painted Stork (Mycteria leucocephala), Asian Openbill (Anastomus oscitans), and Chinese Pond Heron (Ardeola bacchus). The species diversity index of the bird community (H') was 2.73 and the most abundant bird species were Eastern Spotted Dove (Spilopelia chinensis), Eurasian tree sparrow (Passer montanus), Eastern jungle crow (Corvus levaillantii), Oriental magpie robin (Copsychus saularis), and Coppersmith Barbet (Psilopogon haemacephalus). Among 4 microhabitats, birds were found the most in the trees, followed by lawn, grassland, and wetland areas. The small urban parks should be designed with diverse microhabitats to provide various ecological functions to attract and ensure adequate resources for organisms.

Land-use diversity can better predict urban spontaneous plant richness than impervious surface coverage at finer spatial scales

Urban spontaneous plants, that are not intentionally propagated by humans and do not belong to the remnants of the natural habitats, not only occur in green spaces but are also distributed in diverse microhabitats in impervious surface areas. Impervious surface coverage is commonly used in studies on spontaneous plant diversity patterns in human-dominated landscapes; however, the role of habitat diversity (i.e., land-use diversity) has been overlooked. Here, we surveyed spontaneous plant composition and land uses (12 types) in 321 0.25 ha sampling sites on the Chongming District islands, Shanghai, to determine the role of land-use diversity in explaining species richness. We examined the linear relationships between species richness and land-use diversity, and quantified the importance of impervious surface coverage and land-use diversity using the random forest (RF) method. All these analyses were conducted for spatial scales from 0.25 to 5 ha in 0.25 ha increments. We found an overall positive relationship between species richness and land-use diversity, and the RF model predicted approximately 50% of the species richness variation at the smallest spatial scale. However, the positive relationship weakened with spatial scale increase, and a rapid decline in explanatory power occurred for all predictor variables in the RF model. Besides impervious surface coverage, both the vegetated and non-vegetated land-use diversity contributed substantially to the prediction of species richness at finer spatial scales. The findings clarify how land-use diversity, both in green spaces and impervious surface areas, affect urban spontaneous plant richness and should be considered in urban biodiversity conservation strategies at the neighborhood scale.