Multidimensional Scaling Ordination Research Articles

Spotted Knapweed Spread and Plant Community Changes in a Lacustrine Dune System

Perched sand dunes are ecosystems vulnerable to anthropogenic influence along the Great Lakes, including Grand Sable Dunes in Pictured Rocks National Lakeshore along Lake Superior. Spotted knapweed (Centaurea stoebe) is a nonnative plant species that has colonized these dunes and spread into increasingly more areas of the ecosystem. I conducted plant surveys in areas with and without spotted knapweed in 2003, and then resurveyed those areas in 2018. Frequency of spotted knapweed increased in both areas surveyed. Additionally, dominance shifted with spotted knapweed becoming the most important species in the area originally invaded and third most important in the area originally uninvaded. There were approximately two-thirds of species shared between the two survey years, but many of the added species in 2018 were woody. Species richness increased between years, as did species diversity. Nonmetric multidimensional scaling ordination displayed community shifts as convergent succession. While the plant communities in the two areas were rather dissimilar in 2003, they converged as overlapping communities in 2018. Additionally, the shift between years in the area originally invaded was smaller compared to the shift between years in the area originally uninvaded. Due to the continuous evolution of plant communities within sand dune ecosystems, there is a need to monitor changes and quantify nonnative species spread patterns. Dominance by spotted knapweed may be facilitating dune stabilization and converging communities along a modified successional trajectory.

Flora of the Forest at Mountain Lake Biological Station, Giles County, Virginia

Local floras are a basis of biogeography, ecology, evolution, and systematics, and they add value to research sites. Mountain Lake Biological Station is located between 1,150 and 1,319 m elevation in southwestern Virginia on infertile, acidic soils supporting a second-growth forest strongly dominated by Quercus rubra about 150 years old. We sampled vascular vegetation on 352 randomly distributed plots 10m in diameter with 8 subplots of 1 m2 each. The plots contained 175 taxa (including 7 taxa that included 16 lumped species); other fieldwork added 43 species for a total of 227 species in the forest. We excluded disturbed areas around buildings, roadsides, and ponds that harbor many ruderal and invasive species. Average detection probability of a species on a plot was estimated to be 75%. We recorded binary occurrence (present or absent on a plot) and prevalence (occurrence on 0, 1, 2, … 8 subplots per plot) and a set of environmental variables measured in the field or laboratory, or estimated from LIDAR data collected by NEON. Nonmetric multidimensional scaling ordination rejected the null hypothesis of random distributions of herbaceous species among plots. Cluster analysis defined eight groups of plots based on prevalence of herbaceous species to illuminate rejection of the null hypothesis. The environments of these clusters, determined only by their floras, demonstrated the importance of rock type, soils, solar radiation, canopy height, and topography in determining the local distribution of species. Significant differences among assemblages and their environments occurred within a superficially homogeneous forest.

Comparative Analysis of the Ecological Succession of Microbial Communities on Two Artificial Reef Materials.

Concrete and wood are commonly used to manufacture artificial reefs (ARs) worldwide for marine resource enhancement and habitat restoration. Although microbial biofilms play an important role in marine ecosystems, the microbial communities that colonize concrete and wooden ARs and their temporal succession have rarely been studied. In this study, the temporal succession of the microbial communities on concrete and wooden AR blocks and the driving factors were investigated. The composition of the microbial communities underwent successive shifts over time: among the six dominant phyla, the relative abundances of Proteobacteria, Cyanobacteria and Gracilibacteria significantly decreased in wood, as did that of Cyanobacteria in concrete. Operational taxonomic units (OTU) richness and Shannon index were significantly higher in concrete than in wood. Non-metric multidimensional scaling ordination placed the microbial communities in two distinct clusters corresponding to the two substrate materials. The macrobenthic compositions of concrete and wood were broadly similar and shifted over time, especially in the first five weeks. The Shannon index of the microbial communities in concrete and wood increased significantly with the organism coverage. The results provide fundamental data on microbial community succession during the initial deployment of ARs and contribute to understanding the ecological effects of ARs.

Влияние факторов среды на межгодовые изменения макрозообентоса пойменных озер

The changes in depth, temperature, water conductivity, and dissolved oxygen concentration in six floodplain lakes are described in regard to the dynamics of spring flooding and overgrowth by macrophytes. The influence of these factors on the composition and structure of macrozoobenthos communities is analyzed. The observed number of species refers to 60% of the theoretically predicted, which allows us to assume that the fauna has been identified sufficiently enough to analyze the interannual changes. Six families of invertebrates, which form together 55% of the fauna, are the richest in species number. The distribution of species by families also confirms enough data on the fauna representing in the obtained and analyzed samples. Abundance of only two species depend significantly on environmental characteristics; the taxonomic and trophic groups exhibit more links to the environment. Totally, 45 mutually associated species (43.7% of the total list) have been identified; they form 8 groups that are characterized by connectivity of the species composition ranging as 0.28–1.0 link/species, the average connectivity strength of 0.67–0.80, and the strength of species connectivity of 0.38–0.84 (the last index is proposed for the first time). Groups of mutually associated species may be defined as “faunistic cores of communities” confined to certain lakes and/or years of study. According to the redundancy analysis with multidimensional scaling ordination, the environmental factors affect the quantitative characteristics and overall taxonomic richness of communities. The indices, describing the structure of communities, do not depend on the analyzed factors, which is also confirmed by correlation analysis.

Differences in distribution and community structure of plant-parasitic nematodes in pecan orchards between two ecoregions of Georgia.

In Georgia, pecans are commercially grown in the Piedmont and Coastal Plain ecoregions which are characterized by sandy-loam, sandy, and/or clay soils. If well-drained, these soils are suitable for pecan production, but the soil characteristics differ enough between ecoregions in which the plant-parasitic nematode (PPN) communities could differ substantially. We studied PPN communities in pecan orchards to evaluate the potential for ecoregion differences. In total, 11 genera (Helicotylenchus, Hemicycliophora, Heterodera, Hoplolaimus, Meloidogyne, Mesocriconema, Pratylenchus, Paratylenchus, Paratrichodorus, Tylenchorhynchs, Xiphenema) were recovered from pecan orchards in the Piedmont and Coastal Plain ecoregions. However, Non-Metric Multi-Dimensional Scaling ordination, Multi-Rank Permutation Procedure, and Indicator Species Analyses indicated that the pecan PPN communities strongly differed between ecoregions and that different genera were strongly associated with different ecoregions. For 9 of the 11 PPN genera, the maximum counts occurred in Coastal Plain locations, suggesting that the well-drained sandy soils of the Coastal Plain and comparatively ill-drained red clay soils of the Piedmont may be conducive and unfavorable for movement/reproduction of PPNs, respectively.

Impacts of Dryland Cropping Systems on Ground Beetle Communities (Coleoptera: Carabidae) in the Northern Great Plains.

Ground beetles are natural predators of insect pests and small seeds in agroecosystems. In semiarid cropping systems of the Northern Great Plains, there is a lack of knowledge to how ground beetles are affected by diversified cover crop rotations. In a 2-yr study (2018 and 2019), our experiment was a restricted-randomization strip-plot design, comprising summer fallow, an early-season cover crop mixture (five species), and a mid-season cover crop mixture (seven species), with three cover crop termination methods (i.e., herbicide, grazing, and haying). Using pitfall traps, we sampled ground beetles in five 48-h intervals throughout the growing season (n = 135 per year) using growing degree day (GDD) accumulations to better understand changes to ground beetle communities. Data analysis included the use of linear mixed-effects models, perMANOVA, and non-metric multidimensional scaling ordinations. We did not observe differences among cover crop termination methods; however, activity density in the early-season cover crop mixture decreased and in summer fallow increased throughout the growing season, whereas the mid-season cover crop mixture peaked in the middle of the summer. Ground beetle richness and evenness showed a nonlinear tendency, peaking in the middle of the growing season, with marginal differences between cover crops or fallow after the termination events. Also, differences in ground beetle composition were greatest in the early- and mid-season cover crop mixtures earlier in the growing season. Our study supports the use of cover crop mixtures to enhance ground beetle communities, with potential implications for pest management in dryland cropping systems.

Community Characteristics Analysis of Eukaryotic Microplankton via ITS Gene Metabarcoding Based on Environmental DNA in Lower Reaches of Qiantang River, China

Eukaryotic microplankton plays an important role in water biotic community and in maintaining the stability of water ecosystems. Environmental DNA metabarcoding provides the opportunity to integrate traditional and emerging approaches to discover more new species, and develop molecular biotic indices that can be more rapidly, frequently, and robustly used in water quality assessments. In order to examine assemblages of eukaryotic microplankton in lower reaches of Qiantang River, ITS gene metabarcoding technology based on environmental DNA was carried out. As a result, various species of phytoplankton, fungi and zooplankton were annotated on. More phylum, classes and specieses of eukaryotic phytoplankton and zooplankton were found after compared communities taxa based on metabarcoding with that obtained from morphological examination. Nevertheless, Chlorophyceae was the most common assemblage both identified by using these two methods, also Mesocyclops leuckarti and Acanthocyclops bicuspidatus were both found to be the dominant species of Cyclopoida in the river. Additionally, the reads proportions of phytoplankton and zooplankton at the three freshwater sampling sites (Tonglu, Fuyang and Wenyan) decreased as temperature drop. Meanwhile, twenty classes of fungi were annotated on, of which the community characteristic was first researched in the river. There were significant spatial differences in values of Chao1 index for eukaryotic microplankton. Cluster analysis and Non-metric multidimensional scaling ordination further confirmed that the community composition of eukaryotic microplankton at class level for Jiashao-September sample had the most dissimilarity with the others.

Butterflies as an indicator group of riparian ecosystem assessment

Riparian ecosystems play an important role in modulating a range of ecosystem processes that affect aquatic and terrestrial organisms. Butterflies are a major herbivore in terrestrial ecosystems and are also common in riparian ecosystems. Since butterflies use plants for larval food and adult nectar sources in riparian ecosystems, butterfly diversity can be utilized to evaluate riparian ecosystems. We compiled butterfly data from 33 sites in three riparian ecosystem types across the country and compared butterfly diversity in terms of number of species and quality index in relation to riparian environmental variables. Number of butterfly and plant species was not different among three riparian habitat types. Additionally, there was no significant ecological variable to distinguish the butterfly communities on three riparian habitats. Non-metric multi-dimensional scaling ordination showed that butterfly communities in three riparian ecosystem types differed from each other, and butterfly riparian quality index was the main variable for butterfly assemblages. Five indicator species for moor and another five species for riverine riparian ecosystems were identified. Three and one indicator species for moor and riparian ecosystems, respectively, were plant specialists, while 44 butterflies were general feeders, feeding on a wide range of hostplants in several habitats. These results suggest that butterfly species use actively riparian habitats for nectar and larval food, and the butterfly riparian quality index can be employed to track faunal change in riparian habitats, which are frequently threatened by disturbances such as water level and climate changes, and invasive species.

Timber and non-timber forest products in the northernmost Neotropical rainforest: Ecological factors unravel their landscape distribution

The benefits provided by tropical rainforests are unevenly distributed throughout the landscape and are shaped by abiotic and biotic components that influence the spatial distribution and functional traits of the species involved. We tested whether environmental stratification of the rainforest in biophysical Landscape Units (LU), defined by topography and soil, is related to the spatial distribution of diversity, abundance and productivity (standing biomass) of tree assemblages that provide potential forest products (PFP). Considering that different PFP are associated with specific plant traits, we also tested whether a phylogenetic signal exists among the species that comprise specific use categories. Non-metric multidimensional scaling ordinations and permutational analysis of variance were based on the frequency, abundance and productivity of 129 species, the PFP of which were classified as fodder, food, fuelwood, medicinal, melliferous, ornamental, plywood and timber in 15 plots of 0.5 ha each. We constructed a phylogenetic tree of the studied species and analyzed the phylogenetic signal strength (D-statistic) among them. The spatial distribution of diversity and abundance of useful species changes among the LU. Specific PFP can be provided in contrasting habitat conditions, but generally not by the same species. The PFP categories that presented a phylogenetic signal were associated with wood characteristics (fuelwood and plywood) and the palatability of the leaves and reproductive structures (fodder). The Moraceae family was significantly related to fodder and plywood, whereas Meliaceae, Myrtaceae and Sapotaceae were mostly used for fuelwood. The medicinal species presented convergent traits distributed throughout the phylogeny. However, since our study included a broad variety of plant structures, it is possible that phylogenetic dispersion can change if we consider the specific uses within each category. Our findings show that the assemblages of PFP suppliers can be clustered through biophysical units based on soil and topography, and specific categories of PFP are often supplied by phylogenetically related species. This knowledge is fundamental in order to incorporate the high diversity of tree species and their potential uses into productive reforestation and agroforestry programs.

Seasonality affects the community of endophytic fungi in coconut (Cocos nucifera) crop leaves

The diversity of endophytic fungi in healthy coconut palm leaves (Cocos nucifera) was assessed by analyzing fungal isolates from three coconut cultivars (yellow dwarf, green dwarf, and a hybrid cultivar PB121) used agriculturally in Brazil. The influence of season (rainy or dry) on the endophytic fungal community was also analyzed. Overall, 318 fungal isolates were obtained from 972 coconut leaf fragments. The rDNA ITS region was sequenced from representative species of the isolated endophytic fungi and the most common species identified were Nigrospora oryzae, Pestalotiopsis sp., and Zasmidium musae. The alpha diversity of the endophytic fungi was also calculated. Nonmetric multidimensional scaling (NMDS) ordination and permutational analysis of variance (PERMANOVA) revealed significant seasonal effects on the composition of the endophyte community. However, practically no influence was observed on the fungal communities for the different cultivars of coconut.

Sustainability indicators for the integrated assessment of coastal small-scale fisheries in the Brazilian Amazon

A multidisciplinary assessment of the sustainability status of 11 coastal small-scale fishery systems in the Brazilian Amazon was performed using the Rapfish method with 31 indicators representing six evaluation fields (ecological, economic, ethical, institutional, social, and technological). The method employs a constrained multidimensional scaling ordination technique; uncertainty is expressed through Monte Carlo simulation and sensitivity by leverage analysis. Results showed that most fishery systems were ecologically, economically, and socially ‘less satisfactory’ and institutionally and ethically ‘not sustainable’. Fishers have low levels of education and are highly reliant on fishing. They face low income, scarcity of alternative livelihoods, isolation from markets, weak political representation, and lack of regulatory measures and decision-making power. Fisheries target fishes with long life cycles and moderate to high vulnerability. Declining catches, increasing fishing effort and catching power, and competition with other fleets threatens the sustainability of fisheries. Recommendations include moving towards participatory management and governance, supporting the building of cohesive social organizations, and strengthening of human rights. New research and monitoring data and investments in capacity-building in research institutes and management agencies are required. The Rapfish method was employed with revised and new attributes, and the results demonstrate its applicability in data-poor scenarios in developing countries.

Seed bank offers potential for active restoration of mountain meadows

The nitrogen‐fixing legume Lupinus polyphyllus invaded semi‐natural mountainous grasslands across Europe during the last decades. This invasion resulted in degraded habitats through changes in the structure and function of the mountain meadow vegetation. In our study, we analyzed (1) the effects of increasing cover of L. polyphyllus on the seed bank of mountain meadows, and (2) the potential of the seed bank of these stands for active restoration of mountain meadows in terms of species composition and number. We conducted a seed bank analysis on 84 plots with increasing cover of L. polyphyllus in three mountain‐meadow types of the Rhön Biosphere Reserve, Germany. Seedlings from 119 species germinated from the seed bank samples, including 17 Red List species but only a few seedlings of L. polyphyllus. The species composition of the seed bank matched distinct patterns of the three meadow types, but differed from the species composition of the current aboveground vegetation in a nonmetric multidimensional scaling ordination. While the influence of L. polyphyllus on the current vegetation was visible, no effects on the seed bank were apparent. L. polyphyllus had no influence on total seed density, seed density of typical mountain‐meadow species, or species numbers in the seed bank. Only the seeds of the Red List species were significantly related to the cover of L. polyphyllus. We conclude that the seed bank offers potential for active restoration of species‐rich mountain meadows, but species absent from the seed bank have to be added by other measures.

Population structure of Gobiidae in a tropical urban estuary

As spatiotemporal variations in estuaries affect the population structure of species, the study aimed to analyze the distribution of species of the family Gobiidae in the Capibaribe River's estuary city of Recife (northeastern Brazil). Sampling was performed bi-monthly from February 2009 to December 2012 at two sampling stations. The weight-length relationship of the species was determined using potential regression analysis. Density and biomass values were determined for each species per sampling station and season. The Mann-Whitney test was used to compare spatial and seasonal differences in abundance. A non-metric multidimensional scaling ordination was used to assess changes in species composition. Seven hundred eighty-eight individuals were caught. The most representative species of Gobiidae was Ctenogobius boleosoma, followed by Evorthodus lyricus and Gobionellus oceanicus. The relationship between total weight (TW) and standard length (SL) was potential and significant for both C. boleosoma (TW = 0.04SL2.1815) and E. lyricus (TW = 0.0272SL2.795), and both exhibited negative allometric growth. The analysis of the main species' spatial variation demonstrated a significant difference in the number of individuals for C. boleosoma (U = 528; p = 0.000005) and E. lyricus (U = 312; p = 0.000000). No significant difference in abundance was found between the dry and rainy season for either C. boleosoma (U = 1052.2; p = 0.4659) or E. lyricus (U = 1054; p = 0.4726). The two most abundant species have similar habits and customarily inhabit stressful environments. Ctenogobius boleosoma and E. lyricus are residents of the Capibaribe River's estuary, and both move to regions near the outfall of the river in the rainy season.

Assessing anthropogenic disturbance in Estero de Urías coastal lagoon through the lens of annelid distribution

The coastal lagoon Estero de Urías is subjected to several anthropogenic activities and was characterized in 1997 and 2008 through the study of benthic annelids. To reveal the current degree of perturbation, the spatial and temporal distributions of polychaete families and oligochaetes were analyzed. Sediment samples were collected in 2016 and 2017 from six collection sites located downstream of a shrimp farm, small shrimp farms surrounded by mangroves, a thermoelectric plant, a fish processing factory, domestic sewage, and a harbor for fishing fleets. ANOVA revealed significant temporal differences in annelid abundance, but no spatial differences. The Pearson correlations among abundance and environmental variables, a nonmetric multidimensional scaling ordination plot, and a SIMPER analysis did not show clear distribution patterns over the study area. Correlations (Spearman Rank) between common taxa and environmental variables indicated higher dependence of temperature, followed by depth and organic matter on most of these taxa. A canonical correspondence analysis using the abundance of the characteristic species and the environmental variables showed no clear associations among sites. The consistent presence of Capitellidae, Spionidae, Cirratulidae, and Nereididae suggests that the entire system was in a perturbed state during the study period. This differs from the previous characterizations, when different degrees of perturbation were clearly identified and related to each anthropogenic source. The slightly or nonperturbed zones previously detected have been degraded as small farms, tourism, and fishing fleets have increased; however, this interpretation should be considered tentative due to our study's small sample sizes and lack of salinity measurements.

Anatomy of disaster recoveries: Tangible and intangible short-term recovery dynamics following the 2015 Nepal earthquakes

The April/May 2015 Nepal earthquakes and aftershocks had catastrophic impacts on rural households living in biophysical extremes. Recoveries from natural hazards that become disasters have tangible and intangible short- and long-term dynamics, which require linked quantitative and qualitative methods to understand. With these premises in mind, we randomly selected 400 households in two accessible and two inaccessible settlements across two of the highest impacted districts to assess variation in household and settlement recoveries through tangible impacts to infrastructure and livelihood and intangible impacts to place attachment and mental well-being. We conducted household surveys, in-depth interviews, and focus groups over two ten-week intervals at 9 months and 1.5 years after the earthquakes and returned at 2.5 years to share and contextualize results. Previously, we used non-metric multidimensional scaling ordination to illustrate associations among recovery indicators, demographics, and adaptive capacity domains composed of multiple variables. Results indicated that socio-economic status, hazard exposure, livelihood, and displacement influenced recovery outcomes the most. Here, we triangulate and broaden those findings with 797 surveys, 40 interviews, eight focus groups, and eight research return workshops to illustrate the tangible and intangible dynamics of short-term recoveries through three interconnected and multi-faceted thematic sections: 1) inequality; 2) hazards, livelihood, and displacement; and 3) place, uncertainty, and mental well-being. Our contributions include: 1) providing a linked quantitative and qualitative dataset with a random sample collected at two short-term post-disaster time intervals; 2) illustrating how inequalities shape tangible and intangible recovery dynamics; and 3) documenting linkages between recovery and nascent transformations.

Site types revisited: Comparison of traditional Russian and Finnish classification systems for European boreal forests

AbstractQuestionsForest classifications are tools used in research, monitoring, and management. In Finland, the Cajanderian forest site type classification is based on the composition of understorey vegetation with the assumption that it reflects in a predictable way the site's productive value. In Russia, the Sukachevian forest classification is similarly based on understorey vegetation but also accounts for tree species, soil wetness, and paludification. Here we ask whether Cajander's and Sukachev's forest types are effectively the same in terms of species composition, site productivity, and biodiversity.LocationBoreal forests on mineral soils in Finland and the Russian part of Fennoscandia.MethodsWe use vegetation and soil survey data to compare the Cajanderian and the Sukachevian systems in terms of the understorey community composition (that is supposed to define them), soil fertility and tree productivity (that they are expected to indicate), and biodiversity (that is of interest for conservation purposes). We create and employ class prediction models to divide Russian and Finnish sites into Cajander's and Sukachev's types, respectively, based on vegetation composition. We perform cross‐comparisons between the two systems by non‐metric multidimensional scaling ordination and statistical tests.ResultsWithin both systems, the site types formed similar, meaningful gradients in terms of the studied variables. Certain site types from the two systems were largely overlapping in community composition and arranged similarly along the fertility gradient and may thus be considered comparable.ConclusionsThe Cajanderian and the Sukachevian systems were both developed in the European boreal zone but differ in terms of the exact rules by which site types are determined. Our results show that analogous types between the systems can be identified. These findings aid in endeavours of technology and information transfer between Finnish and Russian forests for the purposes of basic or applied ecological research and forest management.

The influence of riparian invasion by the terrestrial shrub Lonicera maackii on aquatic macroinvertebrates in temperate forest headwater streams

The ecology of headwater streams is tightly linked to the riparian zone through organic matter subsidies which are highly susceptible to alteration due to biological invasion. Lonicera maackii is a non-native shrub that is a highly successful invader of headwater stream riparian zones in the American Midwest. We assessed effects on benthic macroinvertebrates across a gradient of invasion intensity from references sites with minimal invasion to a site that had a very heavy invasion. Benthic macroinvertebrates were sampled throughout the year and compositional differences were assessed using Non-metric Multidimensional Scaling ordination, and by comparing the prevalence of sensitive (Ephemeroptera, Plectoptera, and Trichoptera: EPT) and tolerant (Chironomidae) macroinvertebrate taxa. We found strong evidence of variation among macroinvertebrate communities across the invasion gradient (ANOSIM R = 0.215, P = 0.004) and particularly strong separation between one of our reference sites with minimal invasion and the site with the heaviest invasion. Analysis of EPT taxa indicated a significant overall effect and pairwise comparisons indicated that the site with the heaviest invasion had the lowest percentage of sensitive taxa (P < 0.05). Our analysis of chironomids did not yield a statistically discernable effect, although the pattern of the data suggest higher dominance in the site with the heaviest invasion. These stream-scale results bolster prior laboratory and field experiments and provide evidence that terrestrial invasion of L. maackii impacts the benthic community present in headwater streams. These results provide impetus to re-focus stream management recommendations to include practices that control invasive plants in riparian forests.

Relationship of sediment influx to ostracode populations on the variably deforested Luiche and Mahale platform coasts of Lake Tanganyika, Tanzania

We investigated the hypothesis that ostracode populations are sensitive to variations in sediment discharge related to watershed differences at Lake Tanganyika. Many ostracode species are documented to be sensitive to high turbidity which increases during runoff from strong rainfall events and changes in ostracode populations can impact organisms higher in the food web. We compared surficial death assemblages of ostracodes around two sites with extensive shell beds, the highly deforested Luiche Platform area, heavily populated since the 20th Century, and the less deforested Mahale Platform area, with recent population increases, to understand the impacts of increasing sedimentation within and between sites. The study found that whereas the Mahale Platform area is less disturbed, the faunal differences between sites is not large. The data showed high species richness and abundance of ostracodes at 10–20 m depth at both sites, within shell bed zones, with no statistical difference in raw species richness between the sites. The Mahale Mountain area ostracode populations were however statistically more diverse (Shannon H) than at Luiche. We conducted a multi-response permutation procedure and found that the sites are statistically different, but with very small differences in species richness and ostracode abundance. Non-metric multidimensional scaling ordination of species assemblages shows that most samples overlap on both major axes. This study synthesized with ongoing research about shell bed communities in less disturbed regions of the lake will give insights into how conservation projects can be optimized to preserve the lake’s benthic ecosystem from the effects of deforestation.

Seasonal and Temporal Changes in the Kumamoto Oyster Crassostrea sikamea Population and Associated Benthic Macrofaunal Communities at an Intertidal Oyster Reef in China

Oyster reefs (OR) once dominated coastal estuaries but are now one of the most severely impacted marine habitats on Earth. There is little information available regarding the status of natural OR in China. This study examined the seasonal and temporal changes in the Kumamoto oyster Crassostrea sikamea population and associated benthic macrofaunal communities at the largest intertidal OR (Liyashan) of the China Sea in four field surveys (spring and fall in 2013 and 2018). The oyster densities exhibited no evident seasonal variations in either 2013 or 2018 but showed significant temporal changes and declined by 89.66% in spring and 96.27% in fall between 2013 and 2018. The total densities of benthic macrofaunal communities at the reef area of the OR were significantly higher than those at the degraded oyster habitat (DOH) and dramatically decreased by 80.73% in spring and 64.87% in fall between 2013 and 2018. Nonmetric multidimensional scaling ordination indicated the benthic macrofaunal communities differed significantly between the OR and DOH or among the four sampling periods. Analysis of similarity indicated that the benthic communities at the OR had greater seasonal and temporal changes than did those at the DOH, and that temporal changes in benthic communities were greater than seasonal changes at each habitat. The study concluded that the OR had decreased habitat values as the oyster populations and the benthic macrofaunal communities dramatically declined from 2013 to 2018.

Fruit bat diversity patterns for assessing restoration success in reforestation areas in the Philippines

In response to extensive deforestation in the Philippines in the last century, reforestation initiatives have been developed, setting area- or seedling count-based success criteria. However, to sufficiently assess reforestation as an approach to conserving biodiversity and protecting habitats, restoration of ecosystem integrity must be evaluated. Increased recognition of the role of fauna in ecological restoration has led to the evaluation of the role of different groups in assisting recovery and as potential metrics of success. In this study, we used mist netting data to evaluate how richness, abundance, diversity, and composition of fruit bats differ between reforestation areas and nearby secondary forest, and their potential as measures of restoration success. We captured 6564 fruit bats representing 15 species from a sampling effort of 1,994,366 m2·h. Estimated species richness and Simpson indices did not differ significantly between habitat types. Overall abundance was only significantly different in Palinpinon, with more individuals in the reforestation area, while Shannon indices only differed significantly in BacMan. Differences in composition were all found to be statistically significant, based on non-metric multidimensional scaling ordination biplots and permutational MANOVA. Of the three most abundant species captured across all reservations, the generalists Cynopterus luzoniensis and Macroglossus minimus were more abundant in reforestation areas. On the other hand, the forest specialists Haplonycteris fischeri, Harpyionycteris whiteheadi, and Ptenochirus minor showed lower abundances in reforestation areas. While univariate biodiversity metrics did not differ between secondary forests and reforestation areas, the abundance of particular species and the species composition of fruit bats remained distinct between these habitats. We identified specific aspects of the fruit bat assemblage with the potential as metrics of restoration success. To facilitate evaluation of restoration success using changes in faunal assemblage, we recommend the development of sampling protocols and metrics that would standardize this process.