Similarity In Species Composition Research Articles

Macro Land Snail Diversity and Community Assemblage in Selected Forest Fragments of Leyte Island, Philippines

The diversity of land snails in Leyte Island has not been examined over the past few years. To address this, a survey of macro land snails (> 5 mm in shell height and diameter) in selected forest fragments of Leyte was conducted. A total of 120 quadrats (10 x 10 m) were set in three sampling sites (Inopacan, Baybay, and Maasin) that varies in area size – with Baybay being the largest fragment, followed by Inopacan and Maasin. From a total of 592 individuals, 22 macro land snail species and five families were identified. The macro land snail assemblage was dominated by endemic eupulmonates (Order Stylommatophora) and caenogastropods (Order Architaenioglossa). Among eupulmonates, Family Camaenidae had the most species (10), followed by Trochomorphidae and Achatinidae (two each), and Helicarionidae (one). For caenogastropods, all seven species were under Family Cyclophoridae. Cyclophorus appenidiculatus was the most abundant, representing 16.65% of the total number of individuals. Lissachatina fulica, an invasive land snail, was also documented in all sites. A β-dominated community assemblage was revealed by species accumulation curves with sampling efficiency using a completeness ratio of 1, which indicates a highly efficient sampling method. Detrended correspondence analysis indicated high similarity in species composition among study sites, with two unique species (Subulona cylindracea and Hypselostyla boholensis) recorded in Maasin and two incidental records (Obba bigonia and Helicobulinus sarcinosa). This study yielded 15 new records of macro land snail species during the sampling. There were five species (Hemiglypta semiglobosa, Amphidromus maculiferus, Leptopoma perlucidum, Chloritis leytensis, and Obba bigonia) that were documented on earlier records on the island, but 33 of the previously recorded macro land snail species were not encountered in the study. The community ecology patterns were also documented in the fragmented forests of Leyte, which is very important in local malacofaunal conservation and management.

Late quaternary biotic homogenization of North American mammalian faunas

Biotic homogenization—increasing similarity of species composition among ecological communities—has been linked to anthropogenic processes operating over the last century. Fossil evidence, however, suggests that humans have had impacts on ecosystems for millennia. We quantify biotic homogenization of North American mammalian assemblages during the late Pleistocene through Holocene (~30,000 ybp to recent), a timespan encompassing increased evidence of humans on the landscape (~20,000–14,000 ybp). From ~10,000 ybp to recent, assemblages became significantly more homogenous (>100% increase in Jaccard similarity), a pattern that cannot be explained by changes in fossil record sampling. Homogenization was most pronounced among mammals larger than 1 kg and occurred in two phases. The first followed the megafaunal extinction at ~10,000 ybp. The second, more rapid phase began during human population growth and early agricultural intensification (~2,000–1,000 ybp). We show that North American ecosystems were homogenizing for millennia, extending human impacts back ~10,000 years.

Rope bridges provide safe connectivity for the southern brown howler monkey (Alouatta guariba clamitans Cabrera, 1940) in an urban Atlantic Forest remnant

Abstract A southern brown howler monkey (Alouatta guariba clamitans) population occurs in a remnant of Atlantic Forest located inside an urban area of the municipality of São Paulo, Brazil. This population has been heavily anthropogenically impacted by collisions with vehicles, electrocutions on power lines, and falls onto roads. With the aim of reducing these impacts on howler monkeys, we installed four rope bridges in the forest canopy in Fontes do Ipiranga State Park (PEFI). We used mortality data collected within the PEFI to identify areas with high incident rates to place the bridges. The bridges were monitored continuously (24 hours per day) with camera traps for the 12 months following bridge installation (with one exception). The goal of this study was to evaluate the functionality of the bridges in road impact mitigation for the howler monkeys in the PEFI and for other arboreal species. We recorded use of three of the four rope bridges by five of the six arboreal mammal species known to occur in the PEFI with the following frequency: southern brown howler monkey – 60.5% of events, 70.8 events/month; orange-spined hairy dwarf porcupine – Coendou spinosus, 26.1% of events, 31 events/month; black-eared opossum – Didelphis aurita, 7.2% of events, 7.3 events/month, bare-tailed woolly opossum – Caluromys philander, 3.4% of events, 4.3 events/month and marmoset – Callithrix sp., 2.7% of events, 3.38 events/month. The time to first use of the bridges by howler monkeys in the two bridges for which there were data was 2 and 77 days, while other species took longer to habituate (113–344 days). Adult howler monkeys used all parts of the bridges to cross while younger howlers and the smaller species used mostly the longitudinal side lines. Given our findings of rope bridge use by five species in the PEFI, we recommend the installation of rope bridges of this design in other areas with similar species composition.

Public LiDAR data are an important tool for the detection of saproxylic insect hotspots in Mediterranean forests and their connectivity

Light Detection and Ranging (LiDAR) is a remote sensing technique with multiple uses throughout scientific fields. It can also be used to transfer point data measured in the field to broader spatial scales, which might enable the evaluation of habitats over large areas and define biodiversity hotspots. Our study took place in Cabañeros National Park, which is situated in the Mediterranean, namely, central Spain, and its vegetation is dominated by forest and impenetrable scrubland. LiDAR was used to detect veteran trees as key elements for a highly diverse saproxylic community. The saproxylic beetle community inhabiting tree hollows was studied among different forest types and habitats to determine its preferences. We identified potential hotspots for the saproxylic beetle community of tree hollows both inside and outside of the park, as well as the connectivity of suitable habitat patches. This was based on the species response to the spatial partitioning of the landscape. We found that not all potentially suitable forest types hosted the same saproxylic diversity or similar species compositions. In addition, forest distribution and connectivity inside and outside of the park also varied highly among forest types and habitats, where the most diverse deciduous oak forest was also the least connected together with the riparian forest. The evergreen oak forest could act as a habitat linkage for most of the threatened and less mobile species in the park. However, the low connectivity of the most diverse forest types in the park surroundings can compromise the persistence of saproxylic diversity in the near future. We concluded that LiDAR data were an effective tool for estimating saproxylic beetle diversity distribution over large-scale areas in the context of landscapes with low accessibility. Additionally, this tool allowed us to identify the most threatened forest types and critical patches for connectivity persistence where management practices capable of accelerating tree veteranisation could help to increase adequate forest connectivity in the region.

Best practice—Is natural revegetation sufficient to achieve mitigation goals in road construction?

AbstractAimsThe area influenced by road construction is large, and measures to re‐establish vegetation in disturbed areas are routinely carried out to reduce impacts on biodiversity. However, goals of mitigation measures are often unclear, and the effects on biodiversity of mitigation measures is rarely monitored. We assessed the effects of different revegetation treatments (natural revegetation, seeding, planting) on vegetation development along highways, and on wildlife crossings of different age.LocationHighways in southeast Norway.MethodsWe collected data on vascular plant species, vegetation cover and height, soil grain size and organic matter content, and compared the species composition, richness, and diversity of the restored sites with reference plots in the adjacent target vegetation (mature forest).ResultsOur results show a significantly higher richness and diversity in restored plots compared to reference plots, and an increased similarity of species composition over time. Species composition was most similar to reference plots in naturally revegetated plots and seeding seemed to reduce both species and functional trait composition similarity.ConclusionsIt is unrealistic that the defined target vegetation will develop on restored sites. Defining a realistic and achievable target vegetation for each road construction project in relation to land use, adjacent vegetation type and successional stage, as e.g., forest edge instead of forest, would be useful. While this may require more effort for management it will translate to higher mitigation success.

Community structure of benthic macroinvertebrates in native and introduced mangroves of northern Beibu Gulf, China: Implication for restoring mangrove ecosystems

Introduced mangroves are widely used to restore mangrove ecosystems in South China. Results of potential impacts on indicative benthic macroinvertebrates are divergent. We explored the community structure of benthic macroinvertebrates in the mangrove ecosystem of northern Beibu Gulf, China across four habitats: native Avicennia marina mangrove, introduced Laguncularia racemosa mangrove, native-introduced mixed mangrove, and unvegetated intertidal flat. Based on the Hill number, community structure was estimated from the dimensions of estimated species richness, diversity, evenness, and species composition similarity. Benthic macroinvertebrates in the unvegetated flat significantly differed from the other three assemblages in mangroves; introduced L. racemosa mangrove had relatively distinct benthic macroinvertebrate assemblage from the native A. marina and the mixed mangroves, with lower species richness and similarity but higher diversity and evenness. Considering the lack of unanimous conclusion of potential impact on benthic macroinvertebrates under complex species interactions, native mangroves should be of top priority in ecosystem restoration.

Parasite communities of the spotted rose snapper Lutjanus guttatus (Perciformes: Lutjanidae) off the Mexican Pacific coasts: Spatial and long-term inter-annual variations.

A total of 802 individuals of Lutjanus guttatus (Steindachner, 1869) specimens were collected over a 10-year period (August 2012 to February 2021) from four locations on the south-central Pacific coast of Mexico. Their parasite communities were quantified and analyzed to determine if they experience significant spatial and inter-annual variations. Thirty-two taxa of metazoan parasite were recovered and identified: four species of Digenea, four Monogenea, one Cestoda, two Acanthocephala, seven Nematoda, one Hirudinea, and nine of Crustacea (six Copepoda, and three Isopoda). Species richness was greatest among the digenean group, which represented 25% of the total species recovered, followed by the nematodes (22% of total species). Species richness at the component community level (10 to 20 species) was similar to reported richness in other Lutjanus spp. The component communities and infracommunities exhibited a similar pattern: low species richness and diversity, and dominance by a single species, mainly the monogenean Haliotrematoides guttati. Parasite community structure and species composition varied through the years, as well as between sampling locations. Variations were possibly caused by a combination of biotic and abiotic factors which generated notable changes in the infection levels of several component species. However, the similarity in the parasite species composition was high locally for short-term periods (one or two years). This result, therefore, suggests that parasite communities of L. guttatus may be more predictable locally, but only for short-term periods.

Variación en diversidad y composición de especies macrofúngicas a través de diferentes tipos de vegetación en Oaxaca, México

Background: Macromycetes play relevant roles in ecosystem functioning as pathogens, mutualists, and organic matter decomposers. Their diversity and distribution are strongly related to environmental conditions and vegetation types, however, there is a lack of ecological studies assessing which biotic and abiotic factors affect macrofungal communities.
 Questions: Which vegetation type harbors the highest macromycete diversity? Do macromycete diversity and species composition change among forest types? Which are the main environmental factors related to diversity and distribution patterns along the study area?
 Data description: Macromycete species richness and abundance, and environmental variables recorded in temperate forests.
 Study site and dates: Ayoquezco de Aldama, Oaxaca. June-November 2019.
 Methods: Macromycetes were collected twice a month in oak, oak-pine, pine-oak and pine forests, and environmental variables were recorded at each site. Species diversity and composition turnover were calculated using diversity and similarity indexes. The relation between diversity and species composition with environmental variables was determined with statistical analyses.
 Results: A total of 186 species were collected. Oak-dominated forests showed the highest similarity in macromycete diversity and species composition. The observed patterns of diversity and distribution were related mainly to air and soil humidity and temperature, topographic factors, and vegetation structure.
 Conclusions: Macromycete diversity and species composition can conspicuously change in short distances owing to the heterogeneity of habitats and resources provided by woody plants, and the topographic characteristic of the landscape. Vegetation type affects both macromycete diversity and distribution due to its influence on local temperature and humidity.
 
 
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Shopping for Ecological Indices? On the Use of Incidence-Based Species Compositional Similarity Measures

β-diversity has been under continuous debate, with a current need to better understand the way in which a new wave of measures work. We assessed the results of 12 incidence-based β-diversity indices. Our results of gradual species composition overlap between paired assemblages considering progressive differences in species richness show the following: (i) four indices (β-2, β-3, β-3.s, and βr) should be used cautiously given that results with no shared species retrieve results that could be misinterpreted; (ii) all measures conceived specifically as partitioned components of species compositional dissimilarities ought to be used as such and not as independent measures per se; (iii) the non-linear response of some indices to gradual species composition overlap should be interpreted carefully, and further analysis using their results as dependent variables should be performed cautiously; and (iv) two metrics (βsim and βsor) behave predictably and linearly to gradual species composition overlap. We encourage ecologists using measures of β-diversity to fully understand their mathematical nature and type of results under the scenario to be used in order to avoid inappropriate and misleading inferences.

Similar fish species composition despite larger environmental heterogeneity during severe hypoxia in a coastal ecosystem.

Environmental heterogeneity is one of the most influential factors that create compositional variation among local communities. Greater compositional variation is expected when an environmental gradient encompasses the most severe conditions where species sorting is more likely to operate. However, evidence for stronger species sorting at severer environment has typically been obtained for less mobile organisms and tests are scarce for those with higher dispersal ability that allows individuals to sensitively respond to environmental stress. Here, with the dynamics of fish communities in a Japanese bay revealed by environmental DNA metabarcoding analyses as a model case, we tested the hypothesis that larger environmental heterogeneity caused by severe seasonal hypoxia (lower concentration of oxygen in bottom waters in summer) leads to larger variation of species composition among communities. During summer, fish species richness was lower in the bottom layer, suggesting the severity of the hypoxic bottom water. In contrast to the prediction, we found that although the environmental parameters of bottom and surface water was clearly distinct in summer, fish species composition was more similar between the two layers. Our null model analysis suggested that the higher compositional similarity during hypoxia season was not a result of the sampling effect reflecting differences in the alpha or gamma diversity. Furthermore, a shift in the species occurrence from bottom to surface layers was observed during hypoxia season, which was consistent across species, suggesting that the severe condition in the bottom adversely affected fish species irrespective of their identity. These results suggest that larger environmental heterogeneity does not necessarily lead to higher compositional variation once the environmental gradient encompasses extremely severe conditions. This is most likely because individual organisms actively avoided the severity quasi‐neutrally, which induced mass effect‐like dispersal and lead to the mixing of species composition across habitats. By showing counter evidence against the prevailing view, we provide novel insights into how species sorting by environment acts in heterogeneous and severe conditions.

Soil metabolomics and bacterial functional traits revealed the responses of rhizosphere soil bacterial community to long-term continuous cropping of Tibetan barley.

Continuous cropping often leads to an unbalanced soil microbial community, which in turn negatively affects soil functions. However, systematic research of how these effects impact the bacterial composition, microbial functional traits, and soil metabolites is lacking. In the present study, the rhizosphere soil samples of Tibetan barley continuously monocropped for 2 (CCY02), 5 (CCY05), and 10 (CCY10) years were collected. By utilizing 16S high-throughput sequencing, untargeted metabolomes, and quantitative microbial element cycling smart chips, we examined the bacterial community structure, soil metabolites, and bacterial functional gene abundances, respectively. We found that bacterial richness (based on Chao1 and Phylogenetic Diversity [PD] indices) was significantly higher in CCY02 and CCY10 than in CCY05. As per principal component analysis (PCA), samples from the continuous monocropping year tended to share more similar species compositions and soil metabolites, and exhibited distinct patterns over time. The results of the Procrustes analysis indicated that alterations in the soil metabolic profiles and bacterial functional genes after long-term continuous cropping were mainly mediated by soil microbial communities (P < 0.05). Moreover, 14 genera mainly contributed to the sample dissimilarities. Of these, five genera were identified as the dominant shared taxa, including Blastococcus, Nocardioides, Sphingomonas, Bacillus, and Solirubrobacter. The continuous cropping of Tibetan barley significantly increased the abundances of genes related to C-degradation (F = 9.25, P = 0.01) and P-cycling (F = 5.35, P = 0.03). N-cycling significantly negatively correlated with bacterial diversity (r = − 0.71, P = 0.01). The co-occurrence network analysis revealed that nine hub genera correlated with most of the functional genes and a hub taxon, Desulfuromonadales, mainly co-occurred with the metabolites via both negative and positive correlations. Collectively, our findings indicated that continuous cropping significantly altered the bacterial community structure, functioning of rhizosphere soils, and soil metabolites, thereby providing a comprehensive understanding of the effects of the long-term continuous cropping of Tibetan barley.

Higher Plant Conservation Across a Gradient of Increasing Agroecosystems Management Intensity in Western Ethiopia

Human mismanagement of natural forests caused the great loss of ecosystem services because of conversion into modified landscapes. On the other hand, agroecosystems are playing vital role in terms of retaining and conserving certain perennial plants in addition to the small fauna. The main objective of this study is to assess the diversity of woody species and vegetation structure in three coffee systems across an increasing farmers’ management intensity in selected research areas of Western Wollega, Ethiopia. A total of 72 samples (24 per each management systems) were purposively selected from three districts based on the dominant coffee production system and the level of coffee production, which supposed to affect the diversity of tree species for collecting data on woody species. Plant specimens were collected following standard herbarium technique and identified in the field and at national herbarium. A total of 50 woody species were identified. The nonmetric multidimensional scaling (NMDS) ordination and Sorensen distance-based ordination demonstrated that plots of the same coffee system were almost maintained similar species composition and abundance. Diversity of woody species was significantly different among the coffee management systems (P &lt;.0001). Similarly, some of the structural parameters like density, basal area, and shade significantly reduced along the increased coffee management intensity. The study found evidence that the intensification of coffee management was not always the source of biodiversity loss; rather, it is an opportunity for conservation of the locally threatened higher plants. Incorporation of coffee shrubs in the degraded lands or remnant forest patches, integrating coffee in the massive afforestation can be used as an alternative strategy for overstorey plant conservation.

Effects of Soil Amelioration and Vegetation Introduction on the Restoration of Abandoned Coal Mine Spoils in South Korea

In order to ecologically restore coal mine spoils, tolerant species were selected through vegetation surveys on the abandoned coal mine spoils and natural forests established on the poor environment similarly to there. In addition, tolerant species were selected through cultivation experiments in the laboratory. Many C4 plants were included among the tolerant species selected through cultivation experiments. Soil was ameliorated by applying commercial organic fertilizer that can improve both physical and chemical properties of soil at the same time. Vegetation introduced for restoration was prepared by combining plant species tolerant to the degraded environment of coal mine spoils and the reference information. The treatment with a soil ameliorator improved the chemical properties of soil, such as the pH and nutrient contents, and promoted the growth of sample plants significantly. However, additional improvements were required compared with the chemical properties of healthy forest soil. The sites restored by ameliorating soil and introducing tolerant species showed a more similar species composition to the reference sites compared with the afforested and non-restored sites in both lowland and upland areas. However, such restoration did not play a significant role in increasing species diversity or excluding exotic plants. In this respect, more active restoration is recommended.

Bird Communities in Coastal Areas. Effects of Anthropogenic Influences and Distance From the Coast

Urbanization effects have been studied all over the world, documenting impact in species richness, abundances and changes in species communities. Birds have been broadly used as study models. In general, urbanization affects birds, reducing species richness, especially in the urban core, and increasing species richness in areas with intermediate levels of disturbance, such as suburbs. Urbanization also changes species assemblages depending on urban characteristics and resources available, creating habitats for different species. Even when more than half of the cities in the world are on the coast, the effects of urbanization on habitat use of terrestrial and marine birds in coastal urban environments has received little attention. We hypothesized that coastal cities would present different bird diversity in modified marine areas and modified inland areas as terrestrial and marine ecosystems coexist. We predict that modified marine areas will have higher species richness than modified inland areas and natural marine areas. For bird assemblages, we expect to find similar species compositions between sites with similar habitat characteristics more than closeness. We compare habitat use of marine and terrestrial avifauna in the human-modified coastal city of Valparaiso, Chile, characterized by a range of urban developments within city boundaries. We specifically compare corrected bird abundance in six different possible habitats for birds, according to distance to the coast, and human influence. Bird counts (50 m fixed radius) were conducted in winter and spring of 2019. Bird species richness and abundances, corrected by the probability of detection, were estimated. Additionally, species composition and occupancy of bird species in those habitats were calculated. Results show that coastal urban cities can provide different habitats for bird species. Modified inland habitats differ from semi-natural inland habitats and from the modified beaches in species richness and species composition. Environmental heterogeneity in coastal cities seems to allow the coexistence of marine and terrestrial bird species, showing differences in species richness and bird assemblages for marine-inland environments and natural- modified habitats. Results highlight the need to consider these factors for urban planning in order to conserve bird diversity in coastal urban areas.

TROPHIC RELATIONS OF PACIFIC SAFFRON COD &lt;i&gt;ELEGINUS GRACILIS&lt;/i&gt; (TIL.) IN THE ICHTHYOCENES OFF KAMCHATKA AND NORTHERN KURILES

Materials collected during 28 bottom trawl surveys on the shelf and continental slope of Kamchatka and Northern Kuriles from 1996 to 2019 were basicaly used for the research. Analysis of 1980 trawl catches was made, where saffron cod was found. In examined waters off Kamchatka and Northern Kuriles saffron cod coexixted with species from 11 faunistic complexes and 7 ichthyocenes. Maximum similar species compositions of fish communities (&gt;80% similarity) coexisting with saffron cod were obsered among communities in geographically adjacent areas, including Northern Kuriles – Southeastern Kamchatka and Northwestern Kamchatka – Southweatsern Kamchatka. Maximum differences in the fish fauna (&lt;60% similarity) were revealed between districts strongly different in width of their continental shelf: Northwestern Kamchatka – Northern Kuriles and Northwestern Kamchatka – Southeaster Kamchatka. Depending on heat content in different years saffron cod was in the company of different, typical elittoral fish species – Pacific cod, walleye pollock or yellowfin sole. It was found based on the published and observed data, that saffron cod forage competitors and forage objects in most cases belong to elittoral group of the broad-boreal Pacific Ocean faunistic complex.

Ant taxonomic and functional beta-diversity respond differently to changes in forest cover and spatial distance

Habitat change affects both taxonomic and functional biodiversity, and beta-diversity is often used as a metric to describe these changes. Furthermore, spatially closer communities tend to have more similar species compositions (lower beta-diversity). These changes in community composition can be revealed with taxonomic and functional aspects of diversity. We assessed the responses of ant taxonomic and functional beta-diversity to changes in forest cover and spatial distance. We expected that changes in taxonomic and functional beta-diversity along a forest cover gradient would be caused by the replacement of open-habitat ant species by forest-habitat ant species. We sampled ants within twelve landscapes with different forest cover percentages in the southwestern Amazon of Brazil. Both taxonomic and functional beta-diversity of pairwise samples (βBC) were partitioned into their turnover (βBal) and nestedness (βGra) components. Increasing forest cover correlated with increases in taxonomic and functional βBC, however, βBal had a greater contribution to taxonomic βBC and βGra to functional βBC. Taxonomic βBC and βBal and functional βBal increased with spatial distance. Forest-habitat species richness increased, and open-habitat species richness decreased with increasing forest cover, while the richness of habitat-use generalist species did not vary. The loss of environmental heterogeneity may be responsible for generalist species dominance and open-habitat species presence in less-forested landscapes. This leads to great taxonomic replacement, but a nestedness gradient of function. Better land use planning is needed to ensure biodiversity and ecosystem functions of forest habitats in human-modified landscapes.

The effect of tillage and no-tillage system on culturable fungal communities in the rhizosphere and soil of two spelt cultivars

A return to old species cultivated in the past, especially those with high health-promoting and nutritional values, such as spelt (Triticum aestivum ssp. spelta) is being increasingly observed. In addition, due to the increasing use of soil protective cultivation systems in recent years, such as no-tillage cultivation or direct sowing, the aim of the study was to assess the mycobiota of spelt rhizosphere and root-free soil, determine the ratio of potentially pathogenic to antagonistic fungi and assess the impact of cultivation systems on the frequency and biodiversity of fungi. The frequency and species composition were examined in 3-years cultivation of two spelt cultivars. The total number of rhizosphere fungi was significantly higher in the no-tillage system and under the spelt cultivar Franckenkorn compared to the tillage system and the cultivar Badengold. The species richness of the analyzed experimental variants was similar. The dominant group of fungi was the order Hypocreales (Ascomycota). Ninety-five percent of the fungal population from the rhizosphere and 88% of fungi from root-free soil belonged to rare (1–5%) or sporadic species (<1%). Taxa with higher frequency (>5%) in the rhizosphere included: Clonostachys, Gibellulopsis, Rhizopus and Sarocladium, Mortierella, Mucor, Penicillium, Sarocladium and Trichoderma. The cultivation system and plant cultivar affected the occurrence and distribution of fungal populations in the rhizosphere and root-free soil. The similarity of species composition of fungal communities in the rhizosphere and root-free soil was low, while taking into account species frequency, their diversity was high. The ratio of antagonistic to potentially phytopathogenic fungi of spelt rhizosphere deteriorated in the 2nd and 3rd year of wheat cultivation.

Land use cover changes the bird distribution and functional groups at the local and landscape level in a Mexican shaded-coffee agroforestry system

Land-use changes have affected biodiversity and the role it plays in ecological functioning throughout the Neotropics. It is important to understand the response of species to land-use changes to recommend appropriate management and conservation strategies. This is particularly true when land use systems include agroforestry systems, such as shade coffee plantations. In this study, we evaluated the taxonomic diversity of birds and the effect of land-use types (cattle pastures, shade coffee plantations, and forests in late successional stages) on the presence of functional groups at the local and landscape level in a Mexican cloud forest landscape. We carried out monthly bird surveys for one year in 90 circular points with a radius of 25 m (30 points per land use type) in which we compared bird taxonomic diversity using effective diversity or Hill numbers. We analyzed the composition and abundance of bird species and functional groups across land use types using nonmetric multidimensional scaling and tested the effect of predictor variables on functional group abundance at the local and landscape level using ordination methods and generalized linear models. In total, we recorded 134 bird species belonging to 27 families. Bird species richness was highest in late forests. Bird species diversity was high in both late forests and coffee plantations in comparison to cattle pastures. There was a greater similarity in the bird species composition and functional groups in both late forests and coffee plantations compared to cattle pastures. Bird functional groups favored by more complex vegetation structure included forest granivores, small insectivorous flycatchers, and nectarivores, groups that were also present in more diverse plant communities at the local level and by humid forests associated with shade coffee plantations at the landscape level. Avian granivores associated with disturbed environments were negatively related with vegetation complexity and forest cover across scales and omnivores were positively associated with disturbed areas at the landscape level. This study shows the susceptibility of certain bird functional groups to different land use types at distinct spatial scales and highlights the role of shade coffee plantations as a land use type that maintains taxonomic and functional diversity of birds in Neotropical cloud forests.

Seasonal and Interannual Dynamics of Pelagic Rotifers in a Tropical, Saline, Deep Lake

This is the first long-term study (monthly samples at two 4-year intervals: 1998 to 2001 and 2013 to 2016) on rotifers in a saline, deep lake. The pelagic rotifer assemblage of Lake Alchichica is simple and comprised by two species, both new and most likely endemic: Brachionus sp. Mexico (related to B. plicatilis) and Hexarthra sp. (related to H. jenkinae). Similar low species richness and composition are found in other saline lakes associated with salinity. Rotifers in Lake Alchichica were an irregular component of the zooplankton community. Rotifers’ overall abundance (471 ± 1211 ind m−2) and biomass (24 ± 63 mg DW m−2) were low; Brachionus sp. Mexico and Hexarthra sp. contributed similarly to the annual mean abundance (54% and 46%, respectively) and biomass (53% and 47%, respectively). Abundance and biomass were tightly coupled, but there was no regular pattern in their seasonal dynamics. When co-existing, Brachionus sp. Mexico showed a higher abundance than Hexarthra sp. The dominant (≈80%) phytoplankton biomass in Lake Alchichica, the large (35–63 µm) diatom Cyclotella alchichicana, is inedible for rotifers, thus rotifers most probably relied only on nanophytoplankton (≤20 µm). Seasonal and interannual differences in rotifers seem related to food availability (oligotrophy) and probably to biotic interactions (e.g., competition). Rotifer abundance and biomass values in 1998–2001 went down to 12.5% in 2013–2016. Climate change and stochastics events leading to pulses of the rotifers’ food, and biotic interactions seem to be the most plausible explanation.

Variation in the microbial community in bioelectrochemical systems treating sulfamethoxazole wastewater — Identifying key operating parameters and revealing sul gene-harboring host bacteria

A biofilm electrode system (BES), which is the combination of a constructed wetland-microbial fuel cell (MFC-CW) with a biofilm electrode reactor (BER), was used to treat wastewater that contained sulfamethoxazole for three months. The variation in the microbial community, including the microbial diversity, was explored. Furthermore, the key operating factors were identified, and the sul genes-harboring host bacteria were revealed. The results demonstrated that the species richness in the BER was greater than in the MFC-CW, but the Shannon index was susceptible to the run time. The Beta diversity showed that the species composition similarity was primarily clustered according to the position of the BES and then according to the run time. In addition, the principal axis analysis showed that the species composition similarity of the MFC-CW was closer to that of the control sample. Both the BER and MFC-CW were significantly correlated with the voltage and SMX concentration (p < 0.01) at the same correlation level (0.25–0.5). There were 39 phyla during the entire operational period, and the top 9 were Proteobacteria, Bacteroidetes, Chloroflexi, Chlorobi, Acidobacteria, Firmicutes, Actinobacteria, Nitrospirae and Planctomysete. The potential host bacteria of the sul genes, such as Lentisphaerae, Firmicutes, Proteobacteria, and Fusobacteria in the BER and Chlorobi, Caldiserica, Nitrospirae, Actinobacteria, and Planctomycetes in the MFC-CW, were obtained using a Procrustes analysis.