Non-metric Multi-dimensional Scaling Model Research Articles

Botanical Assessments of High-Quality Southern Shrub-Carr and Hardwood Swamp Wetlands in the Undeveloped Lowell Regional Greenspace, Kent County, Michigan

The 2019–2023 Masterplan for Kent County Parks includes the future development of acquired properties that have been designated as the Lowell Regional Greenspace (528 acres), occupying nearly the entirety of Section 22 of Lowell Charter Township in Kent County, Michigan. Four wetlands located in the same drainage basin along Karen Creek in the Lowell Regional Greenspace were inventoried for floristic quality assessments during the summers of 2016, 2018, 2019, and 2021. One of the wetlands was forested and determined to be a southern hardwood swamp community type. The other three wetlands are best classified as shrub-carr communities. In the southern hardwood swamp, we recorded 94 species, of which 87 (92%) are native. A total of 321 species were documented in the three shrub-carrs wetlands combined. The number of species in each shrub-carr site, ranging from 172 to 238, is roughly twice that for the southern hardwood swamp site. Two of the species documented are listed as Special Concern in Michigan, and two are new county records for Kent County, Michigan. A non-metric multidimensional scaling model (NMDS) was run to spatially compare similarities and differences among the sites. The Sørensen Index of Similarity, which was employed to further discern differences between pairs of individual sites, was also useful for assigning plant community types as described by the Michigan Natural Features Inventory (2016). The Floristic Quality Assessments indicate that all four of the wetlands are floristically important statewide; furthermore, the three shrub-carr communities have exceptional conservation value. We discovered that the three shrub-carr sites have a high degree of similarity in their species assemblages, whereas the southern hardwood swamp was markedly different. The high richness and significant floristic quality of the shrub-carr sites highlight the conservation value of these often-overlooked habitats. This study underscores the importance of preserving even small tracts of persisting remnant natural habitats. Our research should be of use to Kent County Parks as they approach development of the Lowell Regional Greenspace into a multiple-use recreational space, as well as to those interested in learning more about how to assess and compare habitat quality of remnant natural areas.

The Performance Evolution of Match Play Styles in the Spanish Professional Basketball League

The aim of this study is to analyse the performance evolution of all, and the dominant, team’s performances throughout an eight-season period within the Spanish professional basketball league. Match-related statistics were gathered from all regular season matches (n = 2426) played during the period 2009–2010 to 2016–2017. The non-metric multidimensional scaling model was used to examine the team’s profiles across seasons and for the most successful (playoff) teams. The main results showed that: 3-point field goals made (effect size, d = 0.61; 90% confidence interval, CI = 0.23; 1.37) and missed (d = 0.72; 90% CI = 0.35; 1.46), and assists (d = 1.27; 90% CI = 0.82; 1.86) presented a positive trend with an increased number of actions across the seasons; 2-point field goals made (d = 0.21; 90% CI = −1.25; 2.02) and missed (d = 0.27; 90% CI = −0.52; 0.92) were decreased; free throws made and missed, rebounds, fouls, blocks, steals and turnovers showed a relatively stable performance. The matrix solution (stress = 0.22, rmse (root mean squared error) = 7.9 × 104, maximum residual = 5.8 × 103) indicated minimal season-to-season evolution with the ordination plot and convex hulls overlapping. The two most dominant teams exhibited unique match patterns with the most successful team’s pattern, a potential benchmark for others who exhibited more dynamic evolutions (and less success). The current findings identified the different performances of teams within the Spanish professional basketball league over eight seasons with further statistical modelling of match play performances useful to identify temporal trends and support coaches with training and competition preparations.

Korarchaeota Diversity, Biogeography, and Abundance in Yellowstone and Great Basin Hot Springs and Ecological Niche Modeling Based on Machine Learning

Over 100 hot spring sediment samples were collected from 28 sites in 12 areas/regions, while recording as many coincident geochemical properties as feasible (>60 analytes). PCR was used to screen samples for Korarchaeota 16S rRNA genes. Over 500 Korarchaeota 16S rRNA genes were screened by RFLP analysis and 90 were sequenced, resulting in identification of novel Korarchaeota phylotypes and exclusive geographical variants. Korarchaeota diversity was low, as in other terrestrial geothermal systems, suggesting a marine origin for Korarchaeota with subsequent niche-invasion into terrestrial systems. Korarchaeota endemism is consistent with endemism of other terrestrial thermophiles and supports the existence of dispersal barriers. Korarchaeota were found predominantly in >55°C springs at pH 4.7–8.5 at concentrations up to 6.6×106 16S rRNA gene copies g−1 wet sediment. In Yellowstone National Park (YNP), Korarchaeota were most abundant in springs with a pH range of 5.7 to 7.0. High sulfate concentrations suggest these fluids are influenced by contributions from hydrothermal vapors that may be neutralized to some extent by mixing with water from deep geothermal sources or meteoric water. In the Great Basin (GB), Korarchaeota were most abundant at spring sources of pH<7.2 with high particulate C content and high alkalinity, which are likely to be buffered by the carbonic acid system. It is therefore likely that at least two different geological mechanisms in YNP and GB springs create the neutral to mildly acidic pH that is optimal for Korarchaeota. A classification support vector machine (C-SVM) trained on single analytes, two analyte combinations, or vectors from non-metric multidimensional scaling models was able to predict springs as Korarchaeota-optimal or sub-optimal habitats with accuracies up to 95%. To our knowledge, this is the most extensive analysis of the geochemical habitat of any high-level microbial taxon and the first application of a C-SVM to microbial ecology.

The relative influence of geographic location and reach-scale habitat on benthic invertebrate assemblages in six ecoregions

The objective of this study was to determine the relative influence of reach-specific habitat variables and geographic location on benthic invertebrate assemblages within six ecoregions across the Western USA. This study included 417 sites from six ecoregions. A total of 301 taxa were collected with the highest richness associated with ecoregions dominated by streams with coarse substrate (19-29 taxa per site). Lowest richness (seven to eight taxa per site) was associated with ecoregions dominated by fine-grain substrate. Principle component analysis (PCA) on reach-scale habitat separated the six ecoregions into those in high-gradient mountainous areas (Coast Range, Cascades, and Southern Rockies) and those in lower-gradient ecoregions (Central Great Plains and Central California Valley). Nonmetric multidimensional scaling (NMS) models performed best in ecoregions dominated by coarse-grain substrate and high taxa richness, along with coarse-grain substrates sites combined from multiple ecoregions regardless of location. In contrast, ecoregions or site combinations dominated by fine-grain substrate had poor model performance (high stress). Four NMS models showed that geographic location (i.e. latitude and longitude) was important for: (1) all ecoregions combined, (2) all sites dominated by coarse-grain sub strate combined, (3) Cascades Ecoregion, and (4) Columbia Ecoregion. Local factors (i.e. substrate or water temperature) seem to be overriding factors controlling invertebrate composition across the West, regardless of geographic location.

Quantitative Study of Trempealeauian (Latest Cambrian) Trilobite Distribution in North America

Faunal lists were compiled for the presence or absence of 94 genera from 16 regions. Four similarity coefficients (Simple Matching, Dice, Jaccard, and Otsuka) were computed for the data matrix in Q mode. The similarity matrices were clustered by both the unweighted pair group method and by single linkage. The dendrograms based on the Simple Matching coefficient are not readily interpretable: coefficients that consider negative matches are unsatisfactory for biogeographic studies. The remaining dendrograms have very similar major structure. Elimination of rare genera, those known from only one locality, reduced the number of genera to 64, but the resulting dendrograms differed little from those based on the full data matrix. With the present data set, the methods used are relatively robust. Ordination of the Dice similarity matrix by principal coordinates analysis and nonmetric multidimensional scaling was also employed. The latter technique produced the best model of the relations between the localities as assessed by correlation between the original distances in multidimensional space and in the reduced 3-dimensional space. In this respect, it is superior to principal coordinates and to both of the clustering techniques that were used. All the methods, however, revealed a broadly similar structure to the data. The nonmetric multidimensional scaling model can be readily interpreted. It confirms the previous division of faunas into these characteristic of the restricted shelf environment and these that inhabited the shelf margin—open-ocean regions. It allows recognition of a North American faunal province that may be divided into two subprovinces, one characteristic of the restricted shelf, the other typically found in the northeastern part of the continent and bearing a shelf margin—open-ocean fauna. We have no strong evidence of a homogeneous faunal belt peripheral to the entire cratonic restricted shelf subprovince. The available evidence shows that the faunas inhabiting this shelf-margin-open-ocean environment were, in contrast, relatively heterogeneous. Dependent on their geographic position, these faunas display, to varying extent, the effect of Asiatic and European influences.