Population Structure Of Species Research Articles

Distribution and Molecular Characteristics of Vibrio Species Isolated from Aquatic Environments in China, 2020.

To understand the characteristics of Vibrio isolates in aquatic environments in China and their public health significance, this study investigated water samples in six cities in China in 2020. A total of 88 sampling locations were included and Vibrio isolates were identified in 81 of them. A total of 143 Vibrio isolates belonging to 16 species were selected for characterization. The population structure of Vibrio species showed great differences among the six cities, indicating regional specificity. The presence of virulence genes was examined for the isolates (n = 78) of five pathogenic Vibrio species. All isolates except one (n = 77) contained at least one virulence gene and isolates belonging to the same species showed very similar virulence gene profiles. Then, 26 isolates from 12 species were examined by multilocus sequence typing and were assigned to 25 STs, of which 24 STs were new. Also, the presence of antibiotic-resistant genes was investigated for all 143 isolates and only three isolates were found to contain genes from aminoglycosides, phenicols, beta-lactams or the tetracycline family. Our results provide valuable insights into the Vibrio community in Chinese aquatic environments and can be applied as guidance for the environmental surveillance of the risk of Vibrio isolates.

Population Study Reveals Genetic Variation and Introgression of Four Deciduous Oaks at the Junction between Taihang Mountain and Yanshan Mountain

Oaks (Quercus spp.) are considered model plants for studying plant evolution and natural gene introgression. Beijing area is at the junction between Taihang Mountain and Yanshan Mountain, and it is an overlapping distribution area of several deciduous oaks native to China. Interspecific hybridization often occurs in sympatric sibling species, resulting in blurred interspecific boundaries and hindering the development of breeding. To have better improvement and protection of these oaks, it is urgently necessary to evaluate the genetic diversity and population structure of these oak species. In this study, we collected eleven populations of four oak species (Q. variabilis, Q. mongolica, Q. dentata and Q. aliena) in the Beijing area. By using the polymorphic SSR markers, we analyzed the genetic variation of the collected 400 individuals, investigated the population structure, and found gene introgression events. Q. variabilis had a clearer genetic background as compared to the other three species. Q. mongolica had a more frequent gene introgression with Q. dentata and Q. aliena. Our data reveal the introgression and genetic diversity of the four oak species native to the Beijing area, laying the foundation for conducting an oak germplasm nursery with a clear genetic background for protection and further improvement.

Speciation of pelagic zooplankton: Invisible boundaries can drive isolation of oceanic ctenophores.

The study of evolution and speciation in non-model systems provides us with an opportunity to expand our understanding of biodiversity in nature. Connectivity studies generally focus on species with obvious boundaries to gene flow, but in open-ocean environments, such boundaries are difficult to identify. Due to the lack of obvious boundaries, speciation and population subdivision in the pelagic environment remain largely unexplained. Comb jellies (Phylum Ctenophora) are mostly planktonic gelatinous invertebrates, many of which are considered to have freely interbreeding distributions worldwide. It is thought that the lobate ctenophore Bolinopsis infundibulum is distributed throughout cooler northern latitudes and B. vitrea warmer. Here, we examined the global population structure for species of Bolinopsis with genetic and morphological data. We found distinct evolutionary patterns within the genus, where B. infundibulum had a broad distribution from northern Pacific to Atlantic waters despite many physical barriers, while other species were geographically segregated despite few barriers. Divergent patterns of speciation within the genus suggest that oceanic currents, sea-level, and geological changes over time can act as either barriers or aids to dispersal in the pelagic environment. Further, we used population genomic data to examine evolution in the open ocean of a distinct lineage of Bolinopsis ctenophores from the North Eastern Pacific. Genetic information and morphological observations validated this as a separate species, Bolinopsis microptera, which was previously described but has recently been called B. infundibulum. We found that populations of B. microptera from California were in cytonuclear discordance, which indicates a secondary contact zone for previously isolated populations. Discordance at this scale is rare, especially in a continuous setting.

Impacts of Industrialization on Plant Species Composition, Diversity, and Tree Population Structure in Tropical Moist Deciduous Forest in Bangladesh

Industrial activities have various effects on biodiversity, posing significant threats to forest ecosystems. The current study describes the species composition, taxonomic diversity, and stand structure at Bhawal Sal forest, Gazipur, Bangladesh, as they are affected by industrialization. To achieve the goal, 30 different categorized industries within the forest were considered sampling points and three distance gradient sites viz. Site-1 = Adjacent to industries (0 m), Site-2 = 160 m distance and Site-3 = 320 m distance from industries were designated as treatments. A total of 90 quadrate plots (10 m × 10 m) were taken randomly, of which 30 plots were from each site. Through forest inventory, 46 species (24 trees, 8 shrubs, 5 climbers, and 9 saplings) were recorded from three sites. The study revealed that the stand density and basal area of mature trees (257 stems ha−1 and 8.06 ± 0.60 m2·ha−1) at Site-1 were significantly lower due to diverse industrial operations than other sites. Statistically, all the biodiversity indices of mature trees; Shannon–Wiener’s index (1.72), Simpsons index (0.82), Margalef’s index (1.38), Pielou’s evenness Index (0.39) was found to be lower at proximity to industries. The lowest species richness (12) of all plants was recorded from Site-1. However, the diameter and height distributions of Site-1 comprised young (10–20 cm·dbh) to medium-sized (20.1–30 cm·dbh) trees, while the medium to large sized (>30 cm·dbh) trees was contained at Site-3 in this study. The population structure of tree species at Site-1 also showed a fluctuating curve. Overall, this study highlights that plant ecosystems and tree population structure have declined tremendously due to industrialization. Hence, the current research could be significant for developing the management framework for the disturbed deciduous forest.

Population Structure of Stagonosporopsis Species Associated with Cucurbit Gummy Stem Blight in Korea.

Gummy stem blight (GSB), a common and serious disease in cucurbits worldwide, is caused by three genetically distinct species: Stagonosporopsis cucurbitacearum (syn. Didymella bryoniae), S. citrulli, and S. caricae. In Korea, however, the three species of Stagonosporopsis have been barely characterized. In this study, 21 Stagonosporopsis isolates were recovered from watermelon (Citrullus lanatus) and muskmelon (Cucumis melo) leaves and stem showing blight symptoms collected from 43 fields in Korea. Sequence analysis performed with an internal transcribed spacer region was not competent to differentiate the Stagonosporopsis isolates. On the contrary, analysis of β-tubulin (TUB) genes and three microsatellite markers, Db01, Db05, and Db06, successfully differentiated Stagonosporopsis isolates. Further sequence analysis identified two Stagonosporopsis species, S. citrulli and S. caricae, and one previously unknown species of Stagonosporopsis. Representative isolates from three species caused dark water-soaked lesions on the detached watermelon and muskmelon leaves with no significant differences in the aggressiveness. Our results indicate that the S. citrulli, S. caricae, and unknown Stagonosporopsis sp. are all causal agents of GSB for both watermelon and muskmelon. This is the first report of a new species and the population structure of Stagonosporopsis species causing GSB in Korea.

Detection of body shape variations in vulnerable snow trout, Schizothorax richardsonii (Gray, 1832) from rivers of the Indian Himalayan Region

Species population structure and composition are components of essential biodiversity variables (EBVs) to measure change in global freshwater diversity. Multiple stressors affect the population structure of coldwater fishes in the Indian Himalayan Region (IHR). In this study, 463 individuals of snow trout, Schizothorax richardsonii were collected from 14 locations on seven rivers of IHR (Satlej, Chenab, Beas and Ravi rivers of Indus basin, and Bhagirathi, Alaknanda and Kosi rivers of Ganges basin) to assess the inter and intra-basin population-level shape variation through landmark-based “geometric morphometrics”. Procrustes ANOVA on the superimposed shape coordinates revealed significant relationship (F = 4.51, p < 0.05) among groups. Principal component analysis (PCA) accounted for 42.37% of the total variance (22.69% for PC1, 19.68% for PC2), indicating overlapping among populations. Canonical variate analysis (CVA) accounted for 66.71% of the total variance (37.07% for CV1 and 29.64% for CV2), indicating non-overlapping between basins and within Ganges basin, and overlapping within Indus basin. Pair-wise distances extracted from PERMANOVA also found to be non-significant (p > 0.05) between Satlej, Chenab, Beas and Ravi rivers, indicating overlapping of samples within the Indus basin, and significant (p < 0.05) between rivers of Indus basin, Alaknanda, Bhagirathi and Kosi river systems, indicating non-overlapping of specimens between these rivers. Overall, results of multivariate analysis indicated four heterogeneous populations of snow trout in the selected rivers based on their shape: 1. Indus basin comprising of Satlej, Chenab, Beas and Ravi rivers, 2. Bhagirathi River, 3. Alaknanda River and 4. Kosi River. This study will be useful in stock identification, and provide a key to climate change and demographic research for developing sustainable management strategies to conserve this threatened species.

Diverged subpopulations in tropical Urochloa (Brachiaria) forage species indicate a role for facultative apomixis and varying ploidy in their population structure and evolution.

Urochloa (syn. Brachiaria) is a genus of tropical grasses sown as forage feedstock, particularly in marginal soils. Here we aimed to clarify the genetic diversity and population structure in Urochloa species to understand better how population evolution relates to ploidy level and occurrence of apomictic reproduction. We explored the genetic diversity of 111 accessions from the five Urochloa species used to develop commercial cultivars. These accessions were conserved from wild materials collected at their centre of origin in Africa, and they tentatively represent the complete Urochloa gene pool used in breeding programmes. We used RNA-sequencing to generate 1.1 million single nucleotide polymorphism loci. We employed genetic admixture, principal component and phylogenetic analyses to define subpopulations. We observed three highly differentiated subpopulations in U. brizantha, which were unrelated to ploidy: one intermixed with U. decumbens, and two diverged from the former and the other species in the complex. We also observed two subpopulations in U. humidicola, unrelated to ploidy; one subpopulation had fewer accessions but included the only characterized sexual accession in the species. Our results also supported a division of U. decumbens between diploids and polyploids, and no subpopulations within U. ruziziensis and U. maxima. Polyploid U. decumbens are more closely related to polyploid U. brizantha than to diploid U. decumbens, which supports the divergence of both polyploid groups from a common tetraploid ancestor and provides evidence for the hybridization barrier of ploidy. The three differentiated subpopulations of apomictic polyploid U. brizantha accessions constitute diverged ecotypes, which can probably be utilized in hybrid breeding. Subpopulations were not observed in non-apomictic U. ruziziensis. Sexual Urochloa polyploids were not found (U. brizantha, U. decumbens) or were limited to small subpopulations (U. humidicola). The subpopulation structure observed in the Urochloa sexual-apomictic multiploidy complexes supports geographical parthenogenesis, where the polyploid genotypes exploit the evolutionary advantage of apomixis, i.e. uniparental reproduction and clonality, to occupy extensive geographical areas.

Population Structure and Spatial Distribution of Tree Species in Lower Montane Forest, Doi Suthep-Pui National Park, Northern Thailand

Plant diversity is important for sustainable development, particularly in watershed areas. This study explored tree population and diversity in a lower montane forest (LMF). A 16-ha permanent plot was established in LMF at Huai Kogma sub-watershed, northern Thailand. All trees with a diameter at breast height ≥ 2 cm were tagged, measured, identified, and their coordinates were mapped. The results showed that 220 species in 139 genera from 63 plant families were found. The dominant families based on species numbers and tree density were Fagaceae, Lauraceae, and Theaceae. The most dominant species were Castanopsis acuminatissima, Schima wallichii, Castanopsis armata, and Styrax benzoides. Diameter classes for climax species frequently followed negative exponential distributions, indicating their populations could be maintained into the future. By contrast, pioneer species, such as Macaranga indica, Morus macroura, and Rhus javanica, had discontinuous distribution, and were mostly found in gap areas, indicating successful regeneration may require high light intensity. Spatial distribution patterns based on Morisita’s index showed that most of the selected species had clumped patterns, particularly those in the Fagaceae family, which were predominantly distributed along the mountain ridge. Tree distribution patterns can affect ecological dynamics, thus reinforcing patterns dependent on local interactions such as the abundance of and distance to available resources. Our finding can aid evaluations of forest sustainability, and support the biodiversity conservation plans. In particular, the selection of suitable species for LMF restoration programs where mixed plantings of pioneer and climax species are planned.

Genetic diversity and population structure of wild and cultivated Crotalaria species based on genotyping-by-sequencing.

Crotalaria is a plant genus that is found all over the world, with over 700 species of herbs and shrubs. The species are potential alternative food and industrial crops due to their adaptability to different environments. Currently, information on the genetic diversity and population structure of these species is scanty. Genotyping-by-sequencing (GBS) is a cost-effective high-throughput technique in diversity evaluation of plant species that have not been fully sequenced. In the current study, de novo GBS was used to characterize 80 Crotalaria accessions from five geographical regions in Kenya. A total of 9820 single nucleotide polymorphism (SNP) markers were obtained after thinning and filtering, which were then used for the analysis of genetic diversity and population structure in Crotalaria. The proportion of SNPs with a minor allele frequency (maf) > = 0.05 was 45.08%, while the Guanine-Cytosine (GC) content was 0.45, from an average sequence depth of 455,909 reads per base. The transition vs transversion ratio was 1.81 and Heterozygosity (He) ranged between 0.01-0.07 in all the sites and 0.04 to 0.52 in the segregating sites. The mean Tajima's D value for the population was -0.094, suggesting an excess of rare alleles. The fixation index (Fst) between the different populations based on the Wright Fst (1943) ranged from 0.0119 to 0.066 for the Eastern-Western and Nairobi-Western populations. Model based techniques of population structure analysis including structure, k-means and cross-entropy depicted eight clusters in the study accessions. Non-model based techniques especially DAPC depicted poor population stratification. Correspondence Analysis (CA), Principal coordinate analyses (PCoA) and phylogenetic analysis identified a moderate level of population stratification. Results from this study will help conservationists and breeders understand the genetic diversity of Crotalaria. The study also provides valuable information for genetic improvement of domesticated species.

Comparison of Woody Species Diversity and Population Structure Along Disturbance Gradient in Babile Elephant Sanctuary, Ethiopia

Abstract The study was conducted at Babile Elephant Sanctuary (BES), to identify and document the list of woody species, and to analyze the diversity, richness, evenness, and population structural status of woody species. The diversity of plant species and population structure of woody species were analyzed from 60 quadrats, each with 20 m x 20 m for trees and 5 m x 5 m for shrubs and climbers, using systematic sampling methods with three levels of disturbances regime, namely, low disturbed (LD), moderately disturbed (MD) and heavily disturbed (HD) sites. Vegetation parameters such as diameter at breast height (DBH), richness, evenness, and density of woody species were recorded. Shannon Weiner Diversity Index was used to analysis vegetation diversity and evenness. A total of 61 woody species were identified in the study area that falls within 29 families and 38 genera of which 50.8 % were shrubs, 39.3 % were trees and the rest 9.83 % were climbers. Fabaceae was represented by the highest number of species (14 species = 22.90). The highest plant species richness was recorded from the low disturbed sites, followed by moderately disturbed and heavily disturbed sites respectively. The population density of vegetation was significantly higher in the MD site, followed by the LD site. The total basal area of LD, MD, and HD were 27.2, 19.8, and 11.2 m2/ha, respectively. LD site had significantly (P= 0.04) highest Shannon’s diversity index value (3.21) than the others two disturbance levels. This result suggests that the consequence of human-induced disturbance on woody species diversity and population structure appeared to be negative depending on the type and intensities of the disturbances.

The spatial structure of an experimental group of domesticated moose (&lt;i&gt;Alces alces&lt;/i&gt; L.)

During the domestication process, it is necessary to take into account the population structure of the wild species. In this paper we analyze a spatial structure of experimental groups of moose in conditions of keeping in pens and forest pastures as well as the allocation of individual species and their groups in ontogenesis driven by the social status of moose. The spatial structure is characterized by the position of individual species and small close-knit groups in relation to each other, by social distances, and by the location of moose habitat in forest pastures. Domesticated moose largely retain the properties of the social and spatial structure of the wild population, which results in an individual-group lifestyle and the formation of distant and close-knit groups. Young moose under one year of age form close-knit associations of significant quantity. Then, by the age of one and a half year, these groups gradually disintegrate, and small cohesive subgroups are formed, which become a part of distant associations characterized by partial synchronization of the behavior of these subgroups. Upon reaching the age of three, domesticated moose mostly exhibit the properties of spatial organization of wild species.

Mansonia spp. population genetics based on mitochondrion whole-genome sequencing alongside the Madeira River near Porto Velho, Rondonia, Brazil.

In high abundance, females of the genus Mansonia (Blanchard) can be a nuisance to humans and animals because they are voraciously hematophagous and feed on the blood of a myriad of vertebrates. The spatial-temporal distribution pattern of Mansonia species is associated with the presence of their host plants, usually Eichhornia crassipes, E. azurea, Ceratopteris pteridoides, Limnobium laevigatum, Pistia stratiotes, and Salvinia sp. Despite their importance, there is a lack of investigation on the dispersion and population genetics of Mansonia species. Such studies are pivotal to evaluating the genetic structuring, which ultimately reflects populational expansion-retraction patterns and dispersal dynamics of the mosquito, particularly in areas with a history of recent introduction and establishment. The knowledge obtained could lead to better understanding of how anthropogenic changes to the environment can modulate the population structure of Mansonia species, which in turn impacts mosquito population density, disturbance to humans and domestic animals, and putative vector-borne disease transmission patterns. In this study, we present an Illumina NGS sequencing protocol to obtain whole-mitogenome sequences of Mansonia spp. to assess the microgeographic genetic diversity and dispersion of field-collected adults. The specimens were collected in rural environments in the vicinities of the Santo Antônio Energia (SAE) hydroelectric reservoir on the Madeira River.

Evidence of Genetic Connectivity among Lyle’s Flying Fox Populations in Thailand for Wildlife Management and One Health Framework

Bats are important reservoir hosts of emerging viruses. Recent viral outbreaks and pandemics have resulted in an increased research focus on the genetic diversity, population structure, and distribution of bat species. Lyle’s flying fox (Pteropus lylei) is widely distributed throughout central Thailand, with most colonies congregating in temples within proximity to humans. A lack of knowledge regarding the genetic connectivity among different colonies hinders the investigation of zoonotic disease epidemiology and wildlife management. In this study, we hypothesized that genetic material may be exchanged between Lyle’s flying fox colonies that live in proximity. We assessed the mitochondrial displacement loop and cytochrome b nucleotide sequences of samples collected from 94 individuals from ten colonies across different roosting sites and detected limited genetic differentiation but increased nucleotide divergence within colonies. This suggests that genetic connectivity among Lyle’s flying fox colonies has experienced frequent and recent gene flow. These findings indicate that this species has maintained demographic equilibrium in a stable population, with a slight expansion event in certain populations. These data provide insights into the dynamics of bat populations, and the genetic knowledge gained presents opportunities for the improved monitoring of bat population structure.

Source–sink recruitment of red snapper: Connectivity between the Gulf of Mexico and Atlantic Ocean

AbstractGeopolitical fishery management boundaries are often misaligned with the ecological population structure of marine species, which presents challenges for assessment and management of these species. Red snapper, Lutjanus campechanus, is an iconic and heavily exploited species in both the US Gulf of Mexico and off the southeastern US Atlantic coast and is managed separately in the two jurisdictions. It is hypothesized that the Atlantic red snapper stock is sustained partially by larval subsidies from the Gulf of Mexico. Here we use a biophysical modeling approach to simulate recruitment of red snapper across the entire Southeastern US region, and quantify rates of larval exchange across management jurisdictions. The biophysical framework simulates realistic red snapper behaviors and traits with respect to spatial distribution and timing of spawning, larval vertical migration and pelagic larval duration, and settlement habitat. Our results suggest that areas of the West Florida Shelf south of Tampa Bay are important sources of larvae for the Atlantic population, supplying as much as one third of the recruitment during some years. Yet, contributions of Gulf‐spawned red snapper to the Atlantic stock are highly dynamic given large variability in spatial and temporal patterns of red snapper recovery in each region. As such, effective management of the Gulf of Mexico red snapper stock, particularly the spawning population in southwest Florida, may have important consequences for the sustainable harvest of red snapper off the Atlantic coast.

The First Data on the Biology of Anatolichthys meridionalis (Actinopterygii, Aphaniidae): an Endemic and Endangered Fish of Turkey (Dalaman River Basin).

Species belonging to the Aphaniidae, extant as well as fossil, are widel distributed along the late-period Tethys Sea coast lines. Among the mentioned genera, Anatolichthys is the genus that includes the 13 species. Anatolia has been a center in the diversity of Anatolichthys. The study is one of the first studies on the growth of the species. On this occasion, in study, it was aimed to examine the growth parameters of the Anatolichthys meridionalis Akşiray, 1948 population, which is an endemic and endangered species in Anatolia. The population structure of endemic species Anatolichthys meridionalis in Gökpınar Spring (Dalaman River basin-Turkey) (37.34° N, 29.44° E) was studied, using 108 fish in October 2019 and September 2020. The growth and reproductive characteristics of A. meridionalis were examined in the study. Males made up 42.59%, females 57.41% of the population. The length-weight relationship and Von Bertalanffy growth equation were W = 0.0112L3.4638, R2 = 0.9793, Lt = 22.97 (1 – e–0.0304 (t+2.834)), respectively. Average growth performance and condition factor are calculated as 1.21 and 1.84, respectively. The gonadosomatic index was found in a maximum value (12.742%) in July and a minimum value (0.545%) in January. Reproduction time was found to be in between of July and September. The mean fecundity and mean egg diameter were found as 147.94 ± 28.03 number/individual/year and 1.35 ± 0.04 mm, respectively. The first maturation was found to be at age I. First maturity length (Lm) was estimated at 23.95 mm for females and 22.04 mm for males. Although the study shows that the species has no problem in finding food and is a population with a wide age range, the presence of invasive species in the habitat, the habitat is directly affected by pollution from agricultural activities, water is drawn by pumps for agricultural activities, and it is narrowly distributed and endangered species, A. meridionalis and its habitat Gökpınar Spring should be protected.

Population genetic structure of the endemic fish Gambusia marshi from the Cuatro Ciénegas basin and its outflow in Coahuila, Mexico

The valley of Cuatro Ciénegas in Coahuila, Mexico, has the highest degree of local endemism of any habitat in North America. Despite the arid desert climate, the basin harbours an extensive system of permanent streams, wetlands, and spring-fed pools, and is divided into two sub-basins by the central Sierra de San Marcos y Pinos. Microsatellite loci were surveyed to infer the genetic diversity and population structure of Gambusia marshi, a poeciliid fish endemic to the Cuatro Ciénegas basin and the Río Salado de Nadadores in north-east Mexico. Bayesian clustering analysis revealed four genetic populations within G. marshi and a major east–west division corresponding to the Sierra de San Marcos y Pinos. Most sample sites exhibited high levels of genetic differentiation, although there is evidence for recent gene flow between some of these locations. The population of G. marshi in Poza Anteojo is extremely divergent, and appears to represent a remnant of a different historical system. The G. marshi in Poza Anteojo should be considered an independent management unit. Documenting the number and distribution of distinct populations of G. marshi provides additional justification for protecting the Cuatro Ciénegas basin from additional water withdrawals and further homogenization via the construction of additional canals. By analysing the population structure of a widespread species within a region containing many range-restricted and endemic species, these results shed new light on historical connections among aquatic ecosystems and raise awareness of the possibility that units of conservation concern may exist in other, more range-restricted taxa in the Cuatro Ciénegas basin and encourage the assessment of their conservation status. The results also have implications for species in arid regions in other parts of the world that may also harbour as yet unrecognized isolated populations worthy of conservation.

Population organization of rare species of the genus Jurinea as an indicator of conservation of steppe ecosystems of the Volga Region (Russian Federation)

The article presents the results of the study of the population structure of rare species of the genus Jurinea (Jurinea polyclonos (L.) DC. s. l. (incl. Ju. tenuiloba Bunge), J. ewersmannii Bunge, J. ledebourii Bunge and J. multiflora (L.) B. Fedtsch.) in the steppe Volga region (European part of the Russian Federation). The species is characterized by rarity and its population characteristics change under the influence of anthropogenic factors. The works were carried out in 2000-2021 using population-ontogenetic methods. The species has insufficient potential for self-regeneration of their natural populations. Demographic indices (Replacement index, Recovery index, Aging index) are low. Ontogenetic spectra of populations are similar in their parameters, the predominant group of individuals are mature generative. Anthropogenic pressure leads to a decrease in the number of individuals, their density, low reproductive activity, and gradual aging of populations.

Latitudinal variation in the woody species diversity and population structure of Lannea microcarpa Engl. and K. Krause in Burkina Faso

Latitude is source of variations of plant species diversity and stand structure. This study aimed to characterize the populations of the African grape tree, Lannea microcarpa, in its range in Burkina Faso. Data were collected according to oriented sampling scheme, based on the presence of the species. Overall, 140 inventory plots of 1000 m2 each were considered across the sub-Sahelian, north-Sudanian and south-Sudanian phytogeographical zones. Tree diameter at breast height (DBH) and total height of L. microcarpa individuals were measured and all woody species in each plot were recorded. A comparative analysis was made between zones for woody flora diversity associated with L. microcarpa, dendrometric and stand structure parameters. The results revealed a total woody flora richness of 109 species. Correlogram analysis revealed that species associated with L. microcarpa differed between phytogeographical zones. Ten species showed a probability of association with L. microcarpa. The density of L. microcarpa populations and the floristic diversity of its habitats decreased significantly (p < 0.001) from sub-Sahelian to south-Sudanian zones. The diameter classes’ structure in the three phytogeographical zones revealed unstable populations with a predominance of intermediate classes compared to extreme classes. The height structure of juveniles is marked by a poor transition between the different classes, showing unpredictable regeneration of L. microcarpa in the three phytogeographical zones. The results of this study draw attention to the need to adopt conservation measures for the species. In this sense, the data on the comparative demographic characteristics can serve as a basis for the implementing of adequate management strategies of natural populations of the species across its distribution range in Burkina Faso.

Reproductive strategies and population characteristics of key Cladocera species in the Sea of Marmara

Zooplankton is an essential component of marine ecosystems, with Copepoda and Cladocera being the most important zooplankton groups in all the world’s seas. In the Sea of Marmara, Cladocera has the highest participation in zooplankton abundance. Here we investigated reproductive strategies and population characteristics of four Cladocera species; Penilia avirostris, Pleopis polyphemoides, Evadne nordmanni, and Pseudoevadne tergestina in the Sea of Marmara, northeastern part of Mediterranean Sea. Reproduction strategy, fecundity, and embryonic development of four Cladocera species were achieved. During our study period from 2004 to 2008, there was an extreme jellyfish bloom caused by Liriope tetraphylla and following mucilage event occurred between the years 2006 and 2008. Thus, we also compared the change in phenology and reproductive strategy of cladocerans amongst periods characterized by extreme events and against a suite of environmental parameters. The most dominant Cladocera species in the Sea of Marmara were Penilia avirostris and Pleopis polyphemoides. The population structures of Cladocera species according to their reproductive strategies, parthenogenetic female individuals provided rapid exponential reproduction, and were dominant at 60%–100%. Parthenogenetic fecundity success was found significantly different among Cladocera species. The most remarkable result during the study period was observation of increase in embryo production while populations were in decrease.

Genetic Diversity and Population Structure of Psidium Species from Restinga: A Coastal and Disturbed Ecosystem of the Brazilian Atlantic Forest.

The Atlantic Forest is one of the most threatened biomes in the world. Here, we use a common set of microsatellite markers to assess the genetic diversity and population structure of three species from the genus Psidium (P. guajava, P. macahense, and P. guineense), located in a disturbed environment of the Atlantic Forest, the restinga, in Espírito Santo, Brazil. Psidium guajava populations presented the highest number of alleles (95) followed by P. guineense (81) and P. macahense (68). The genetic variability was high (P. guajava = 0.71; P. guineense = 0.74; P. macahense = 0.63), with greater variation within populations (72 to 84%) than among populations (15 to 27%), reflecting elevated values of genetic differentiation (P. guajava, FST: 0.15; P. macahense, ØST: 0.27; P. guineense, ØST: 0.21). The populations were clustered into two main groups and considered moderately structured. This is the first report of genetic studies and evidence of polyploidy to P. macahense. Our results may provide information that can be used in management and conservation strategies, to preserve the diversity of Psidium populations.