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1.
Rev. biol. trop ; Rev. biol. trop;72(1): e52916, ene.-dic. 2024. tab, graf
Artigo em Espanhol | SaludCR, LILACS | ID: biblio-1559320

RESUMO

Resumen Introducción: Varias presiones antrópicas sufren los ecosistemas acuáticos del piedemonte llanero en Colombia. La respuesta a estresores ambientales aún se desconoce en organismos bioindicadores como Leptohyphidae. Objetivo: Determinar la diversidad de ninfas de Leptohyphidae del río Quenane-Quenanito, en dos periodos hidrológicos contrastantes y su relación con algunas variables fisicoquímicas. Métodos: En diciembre (2014) y febrero (2015) se recolectaron organismos con red Surber en seis estaciones a lo largo del río. Se analizó la diversidad alfa y beta y se aplicó análisis de redundancia y modelos lineales generalizados con el fin de establecer la relación entre los taxones y las variables ambientales. Resultados: Se identificaron 369 organismos pertenecientes a cuatro géneros (Amanahyphes, Traverhyphes, Tricorythopsis y Tricorythodes), dos especies y ocho morfoespecies. Se reporta por primera vez para el departamento del Meta Amanahyphes saguassu. Se registró la mayor diversidad de ninfas en la transición a la sequía y la mayor abundancia en sequía. La diversidad beta señaló que la configuración del ensamblaje cambia a nivel espacial y temporal. Conclusiones: Los organismos de Leptohyphidae prefieren hábitats de corrientes, particularmente en el periodo de sequía, donde hallan alimento (hojarasca, detritos) y refugio para establecerse exitosamente; actividades antrópicas como la urbanización afectan notablemente la diversidad. La alta diversidad registrada en este pequeño río de piedemonte llanero refleja la necesidad de incrementar este tipo de trabajos y esfuerzos de recolección de material de estudio en la región.


Abstract Introduction: Various anthropic pressures affect the aquatic ecosystems of the foothills of Colombia. The response to environmental stressors is still unknown in bioindicator organisms such as Leptohyphidae. Objective: To determine the diversity of Leptohyphidae nymphs of the Quenane-Quenanito river, in two contrasting hydrological periods and its relationship with some physicochemical variables. Methods: In December (2014) and February (2015), organisms were collected with a Surber net at six stations along the current. Alpha and beta diversity was analyzed and redundancy analysis and generalized linear model were applied to establish the relationship between taxa and environmental variables. Results: Were identified 369 organisms belonging to four genera (Amanahyphes, Traverhyphes, Tricorythopsis, and Tricorythodes), two species, and eight morphospecies. Amanahyphes saguassu is reported for the first time for the Meta department. High diversity of Leptohyphidae nymphs was recorded in the transition to drought season and greater abundance in drought. Beta diversity indicated that the configuration of the assemblage changes spatially and temporally. Conclusions: Leptohyphidae organisms prefer fast habitats, particularly in the dry period where they find food (leaf litter, detritus) and shelter to establish themselves successfully; anthropic activities such as urbanization notably affect diversity. The high diversity recorded in this small river in the foothills of the plains reflects the need to increase this type of works and collection efforts of study material in the region.


Assuntos
Animais , Ephemeroptera/classificação , Qualidade da Água , Colômbia , Insetos/classificação
2.
Ecology ; : e4438, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39355992

RESUMO

A soil seed bank is the collective name for viable seeds that are stored naturally in the soil. At the species or population level, the ability to form a seed bank represents a strategy for (re)colonization following a disturbance or other change in the local environmental conditions. At the community level, seed banks are thought to buffer local diversity during periods of environmental change and are often studied in relation to the potential for passive habitat restoration. The role that seed banks play in plant population and community dynamics, as well as their importance in the agricultural sector, means that they have been widely studied in ecological research. This database is the result of a comprehensive literature search, including all seed bank studies from the Web of Science from which data could be extracted, as well as an additional search of the Russian language literature. The database contains information on the species richness, seed density, and/or seed abundance in 3096 records from at least 1929 locations across the world's seven continents, extracted from 1442 studies published between 1940 and 2020. Records are grouped into five broad habitat categories (aquatic, arable, forest, grassland-including shrubland-and wetland), including information relating to habitat degradation from, or restoration to other habitats (total 14 combinations). Sampling protocols were also extracted for each record, and the database was extensively checked for errors. The location of each record was then used to extract summary climate data and biome classification from external published databases. The database has several potential uses. The large geographical spread relative to many other global biodiversity datasets is relevant for investigating patterns of diversity in biogeographical or macroecological contexts. Habitat type and status (intact, degraded, and restored) can be used to provide insights for biodiversity conservation, while the potential effects of sampling method and effort can be used to inform optimized data collection for future seed bank studies. This database is released under the CC-BY license.

3.
Ecol Evol ; 14(10): e70316, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39376476

RESUMO

Invasive alien plant species (IAPS) pose a serious threat to overall plant biodiversity across the globe. Nepal's national parks and protected areas are not devoid of the impact of IAPS. Unfortunately, there is a substantial gap in knowledge regarding the extent and impact of invasion in protected areas of Nepal. This study assessed the impact of invasive alien plant species on the resident plant species of the Koshi Tapu wildlife reserve. After a preliminary field observation, we selected five major IAPS in the area, Mesosphaerum suaveolens, Chromolaena odorata, Ipomoea carnea, Lantana camara, and Mikania micrantha for this study. Ten pairs of adjacent plots sized 4 m × 4 m were surveyed for each invasive species, comprising diverse vegetation types. Each pair consisted of one "invaded plot" where the invasive species was dominant with cover greater than 50%, and another "uninvaded plot" laid out in an adjacent area with similar site conditions but without the invasive species. We calculated the Sørensen Index of Similarity for each paired plot. Wilcoxon rank-sum test was employed to compare ecological parameters between invaded and uninvaded plots for various plant species. Similarly, the difference in impact between each of the five invasive species was assessed using the Kruskal-Wallis test. Species richness varied significantly between invaded and uninvaded plots for C. odorata and I. carnea. The most significant impact on species composition of invaded communities (39.6%) was observed for C. odorata. The cover of the other dominant species varied significantly between invaded and uninvaded plots for all five species studied. The Kruskal-Wallis test showed no significant difference in the impact caused by the five studied invasive species on Species richness, Shannon-Wiener diversity index, species evenness, and height of dominant species. However, a significant difference was observed between the impacts of five studied invasive species and the cover of other dominant species. The crown cover of dominant species decreased much more in the invaded plots of L. camara and M. micrantha than in other species. Specialized management efforts are required to control highly invasive species, such as C. odorata and I. carnea, alongside proactive measures to prevent further spread in ecologically sensitive areas.

4.
J Anim Sci ; 2024 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-39460974

RESUMO

Contributions to gene diversity and allelic richness were computed in a total of 2,260 domestic pig genotypes, sharing 53,626 autosomal SNPs, belonging to 98 pig subpopulations worldwide (41 Asian, 696 genotypes; 20 American, 262 genotypes; and 37 European, 686 genotypes), using 616 pig samples belonging to six different Cosmopolitan pig breeds as an outgroup, to ascertain if local pig subpopulation can be considered reservoirs of genetic diversity for the whole domestic pig species worldwide. Assessments were carried out for the whole dataset and separately for the American-European and Asian subsets. Effective population size was computed at the subpopulation level using molecular coancestry and linkage disequilibrium information to ensure that estimates of contributions to diversity were not affected by demographic issues. Most American and European pig subpopulations tended to have favorable contributions to both gene diversity and allelic richness. However, contributions to allelic richness were more consistent than those obtained for gene diversity, whether the computations are performed using either the whole dataset or the American-Asian subset, suggesting that allelic richness can be a key parameter to identify putative reservoirs for the species. The Asian pig subpopulations never contributed favorably to the allelic richness of the domestic pig metapopulation. Although these results can partially be explained by the highly divergent origins of the American-European and the Asian pig subpopulations, it cannot be discarded that the results obtained for the Asian subpopulations are biased due to a worse calling performance of the pig SNP arrays used for genotyping. The use of other potentially less biased sources of genotypic information is advisable to compare the Asian and American-European pig subpopulations genetic diversity.

5.
Front Plant Sci ; 15: 1396004, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39445146

RESUMO

Introduction: The impacts of climate change can be profound in many ecosystems worldwide, including drylands such as arid and semi-arid scrublands and grasslands. Foundation plants such as shrubs can provide microclimatic refuges for a variety of taxa. These shrubs can directly influence micro6 environmental measures, and indirectly increase the local environmental heterogeneity as a result. We examined the hypothesis that, in comparison to an open gap, foundation shrubs improve the microclimate beneath their canopy and that microclimate is in turn a significant predictor of annual vegetation. The following predictions were made: 1) mean air temperature (NSAT), ground temperature (SGT), and vapour pressure deficit (VPD) will be significantly lower under the shrubs than in the open microsites; 2) shrub canopy size predicts microclimate; 3) site-level aridity estimates and percent shrub cover influence annual plant abundance and richness; and 4) the site13 level mean of NSAT and VPD predict annual plant abundance and richness. Methods: Our study took place in Southwestern California, U.S.A. We used a handheld device with a probe to measure microclimatic variables such as near-surface air temperature (NSAT), near-surface relative humidity (NSRH), and surface ground temperature (SGT) at the shrub species Ephedra californica and in the open gap, across six sites in California, United States. Air temperature and RH were then used to calculate VPD. The mean number of vascular plant species across each site was also recorded. Results & discussion: Only SGT was significantly reduced under shrub canopies. Canopy volume was not a significant predictor of all three microclimatic variables, demonstrating that even small, low-stature shrubs can have facilitative effects. Furthermore, total shrub cover and aridity at sites significantly predicted mean plant richness and abundance. There were significantly more plants associated with shrubs and there were significantly more species associated with the open. Mean air temperature and VPD at the site-level significantly predicted vegetation abundance and richness, though microsite-level differences were only significant for richness. Foundation shrubs are a focal point of resiliency in dryland ecosystems. Understanding their impact on microclimate can inform us of better management, conservation, and restoration frameworks.

6.
Sci Total Environ ; : 177031, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39447893

RESUMO

Human activities alter biomass, nutrient availability, and species dominance in grasslands, impacting their richness, composition, and biomass production. Stability (invariability in time or space) can inform the predictability of plant communities in response to human activities. However, this measure has been simplistically analyzed for temporal (interannual) changes in live biomass, disregarding their spatial stability and the temporal stability of other plant community attributes. Moreover, the simultaneous analysis of temporal and spatial stabilities of plant communities has been scarcely assessed. Here, we test how biomass removal and nutrient addition simultaneously modify the temporal and spatial stabilities of plant richness (α diversity), composition dissimilarity (ß diversity), aboveground live biomass, and the role of plant species dominance in the stability responses. We conducted a factorial experiment of biomass removal (grazing, mowing, or intact -no removal-) and nutrient addition (unfertilized or fertilized with nitrogen, phosphorus, and potassium) in a temperate grassland of Argentina, South America. We replicated the experiment in 6 blocks over 10 years to estimate the temporal and spatial stabilities of the plant community. The spatiotemporal stability of plant richness and composition dissimilarity decreased in the intact grassland, while the temporal stability of live biomass increased, compared to the grazed and mowed grasslands. Nutrient addition reduced the spatiotemporal stability of live biomass and the spatial stability of plant richness. The stability of species richness as well as that of composition dissimilarity was negatively associated with plant dominance, while the live biomass stability was not. Our results suggest that simplifying the effect of biomass removal and nutrient addition on grassland stability is not feasible, as plant diversity stability responses are not surrogates for biomass stability. The contrasting spatiotemporal stability responses of plant diversity and biomass represent a step forward in predicting human activities' impact over time and across space in temperate grasslands.

7.
Neurosci Conscious ; 2024(1): niae035, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39445136

RESUMO

The question of the richness (or sparseness) of conscious experience has evoked ongoing debate and discussion. Claims for both richness and sparseness are supported by empirical data, yet they are often indirect, and alternative explanations have been put forward. Recently, it has been suggested that current experimental methods limit participants' responses, thereby preventing researchers from assessing the actual richness of perception. Instead, free verbal reports were presented as a possible way to overcome this limitation. As part of this approach, a novel paradigm of freely reported words was developed using a new metric, intersubjective agreement (IA), with experimental results interpreted as capturing aspects of conscious perception. Here, we challenge the validity of freely reported words as a tool for studying the richness of conscious experience. We base our claims on two studies (each composed of three experiments), where we manipulated the richness of percepts and tested whether IA changed accordingly. Five additional control experiments were conducted to validate the experimental logic and examine alternative explanations. Our results suggest otherwise, presenting four challenges to the free verbal report paradigm: first, impoverished stimuli did not evoke lower IA scores. Second, the IA score was correlated with word frequency in English. Third, the original positive relationship between IA scores and rated confidence was not found in any of the six experiments. Fourth, a high rate of nonexisting words was found, some of which described items that matched the gist of the scene but did not appear in the image. We conclude that a metric based on freely reported words might be better explained by vocabulary conventions and gist-based reports than by capturing the richness of perception.

8.
New Phytol ; 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39439371

RESUMO

Multispecies planting is an important approach to deliver ecosystem functions in afforestation projects. However, the importance of species richness vs specific species composition in this context remains unresolved. To estimate species or functional group richness and compositional change between two communities, we calculated nestedness, where one community contains a subset of the species of another, and turnover, where two communities differ in species composition but not in species richness. We evaluated the effects of species/functional group nestedness and turnover on stand productivity using 315 mixed plots from a pool of 40 tree species in a large forest biodiversity experiment in subtropical China. We found that the greater the differences in species or functional group nestedness and turnover, the greater the differences in stand productivity between plots. Additionally, the strong effects of both nestedness and turnover on stand productivity developed over the 11-yr observation period. Our results indicate that selection of specific tree species is as important as planting a large number of species to support the productivity function of forests. Furthermore, the selection of specific tree species should be based on functionality, because beneficial effects of functional group composition were stronger than those of species composition.

9.
Ecol Evol ; 14(10): e70095, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39463741

RESUMO

Given that terrestrial ecosystems globally are facing the loss of biodiversity from land use conversion, invasive species, and climate change, effective management requires a better understanding of the drivers and correlates of biodiversity. Increasingly, biodiversity is co-managed with aboveground carbon storage because high biodiversity in animal species is observed to correlate with high aboveground carbon storage. Most previous investigations into the relationship of biodiversity and carbon co-management do not focus on the biodiversity of the species rich plant kingdom, which may have tradeoffs with carbon storage. To examine the relationships of plant species richness with aboveground tree biomass carbon storage, we used a series of generalized linear models with understory plant species richness and diversity data from the USDA Forest Service Forest Inventory and Analysis dataset and high-resolution modeled carbon maps for the Tongass National Forest. Functional trait data from the TRY database was used to understand the potential mechanisms that drive the response of understory plants. Understory species richness and community weighted mean leaf dry matter content decreased along an increasing gradient of tree biomass carbon storage, but understory diversity, community weighted mean specific leaf area, and plant height at maturity did not. Leaf dry matter content had little variance at the community level. The decline of understory plant species richness but not diversity to increases in aboveground biomass carbon storage suggests that rare species are excluded in aboveground biomass carbon dense areas. These decreases in understory species richness reflect a tradeoff between the understory plant community and aboveground carbon storage. The mechanisms that are associated with observed plant communities along a gradient of biomass carbon storage in this forest suggest that slower-growing plant strategies are less effective in the presence of high biomass carbon dense trees in the overstory.

10.
ISME Commun ; 4(1): ycae119, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39464510

RESUMO

Periphytons serve as critical microbial nutrient sinks at the soil-water interface, influencing biogeochemical cycles and nutrient migration in paddy fields. Despite their importance, the impact of accumulated intracellular nutrients on the spatial dynamics and community assembly of periphytons, particularly their microeukaryote communities, remains unclear. To address this gap, we examined the nutrient accumulation potential and its effects on microeukaryotes in periphytons from 220 paddy fields spanning up to 3469 km across three temperature zones. Our study reveals that the periphytons exhibit varying capacities to accumulate carbon, nitrogen, and phosphorus, leading to imbalanced intracellular nutrient stoichiometries (carbon-to-nitrogen ratio = 10.3 ± 2.1, carbon-to-phosphorus ratio = 30.9 ± 13.1, nitrogen-to-phosphorus ratio = 3.1 ± 1.3). This stoichiometric imbalance induces intracellular environmental heterogeneity, which partially influences the local species richness of microeukaryotic communities and their regional structural variations on a large scale. Contrary to the typical latitudinal diversity gradient theory, local microeukaryotic species richness follows a distance-decay model, with both deterministic and stochastic processes contributing to community assembly. These results underscore the complex interplay of environmental filtering, species interactions, and dispersal dynamics in shaping the structure and adaptability of microeukaryotic communities within periphytons. This study contributes to a broader understanding of the factors driving regional structural variations of microeukaryotes at the soil-water interface in agricultural landscapes.

11.
PeerJ ; 12: e18343, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39465160

RESUMO

Reptiles are one of the most diverse groups of vertebrates in the world that are distributed in almost all ecosystems. Many of these studies have focused on exploring their diversity patterns across different environments; and recent studies on reptile alpha and beta diversity have incorporated a multifaceted approach into their analysis to have more comprehensive evaluations. This study presents an assessment of the taxonomic diversity of reptile patterns using methods that incorporate the assessment of higher taxa. Likewise, the taxonomic dissimilarities between reptile communities in the physiographic regions of the state of Jalisco were analyzed. Evaluations for the groups of snakes and lizards independently are presented. We use the taxonomic distinctiveness index that assesses the complexity of the taxonomic structure of communities through hierarchical classification above the species level to measure the relationships between taxa. The dissimilarity of the taxonomic structure in each community was also analyzed. Beta diversity partitions were performed to identify the contribution of turnover and the differences in richness. We determined that alpha diversity of species and higher taxa maintain different patterns, indicating that Jalisco presents regions with overrepresentation of reptile families and genera, as well as regions with an opposite trend. The representation of higher taxa is higher in the lizard group, although in terms of species richness snakes are the most prominent group. The turnover is the most important component at species and higher taxa, with similar values for lizards and snakes. The findings presented show that incorporating phylogenetic information about species through taxonomic relationships provides complementary information that species diversity per se, especially at the level of alpha diversity.


Assuntos
Biodiversidade , Lagartos , Répteis , Serpentes , Animais , México , Répteis/classificação , Lagartos/classificação , Serpentes/classificação , Ecossistema
12.
PeerJ ; 12: e17924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39399437

RESUMO

Our research addresses the pressing need to assess biodiversity in the face of increasing habitat destruction and species extinctions. Several researchers have modelled conventional measures to assess biodiversity. Every measure evaluates biodiversity by considering different properties. Among them Simpson and Shannon indices are widely used, they primarily focus on species richness and abundance, overlooking the importance of rare or unique species. This limitation makes it challenging to identify which species drive changes in biodiversity and hampers conservation efforts. Moreover, these measures are sensitive to sample size and biased towards dominant species, leading to inaccurate estimations. To overcome these challenges, we propose a novel mathematical model that provides a comprehensive assessment of biodiversity. Our model accounts for species dominance, addresses sample size sensitivity, and highlights the significance of rare species within a community. By applying our measure to real-time scenarios and comparing it with traditional methods using the same dataset, proposed measure demonstrated its efficacy in capturing biodiversity dynamics over time.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/métodos , Modelos Teóricos , Ecossistema , Animais
13.
Biodivers Data J ; 12: e129475, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39399758

RESUMO

Background: The Atlantic Forest is one of the most diverse and threatened phytogeographical domains in the world. Despite that, it includes regions with poor floristic knowledge, even in protected areas. Although the importance of protected areas in conserving the Atlantic Forest hotspot is undisputed, it is necessary to recognise the floristic richness of these areas to propose effective conservation actions. In this sense, online databases have proved to be a promising tool for compiling species lists with relevant biodiversity information. This study is based on the list of vascular plants of the "Parque Estadual da Pedra Selada", published in the "Catálogo de Plantas das Unidades de Conservação do Brasil". It summarises the species richness, endemism and conservation status of this protected area. New information: The published list of vascular plants was based on data obtained from herbarium collections available in online databases. A total of 303 species have been recorded for the "Parque Estadual da Pedra Selada," of which 297 are native to Brazil, 78 are endemic to the Brazilian Atlantic Forest, and seven are endemic to the State of Rio de Janeiro. More than 60% of the species are woody, and more than 40% are trees. Eight threatened species (Endangered - EN and Vulnerable - VU), of which five are endemic to the State of Rio de Janeiro, are housed in this protected area. One species was classified as Data Deficient (DD). Our results increase the knowledge of the Atlantic Forest flora in the State of Rio de Janeiro and support effective conservation planning for this protected area.

14.
Artigo em Inglês | MEDLINE | ID: mdl-39402984

RESUMO

Previous research has found that self-compassion enhances well-being outcomes such as happiness and meaning in life. However, little is known about the link between self-compassion and psychological richness, a recently introduced concept of well-being. Thus, an exploration of the relationship between self-compassion and psychological richness is necessary to gain a comprehensive understanding of the association between self-compassion and well-being. To address this issue, this study investigated the temporal directionality of their relationship within a cohort of Chinese college students, utilizing a two-wave longitudinal approach. Using a cross-lagged model, the results revealed that the self-compassion could predict psychological richness 3 months later, and conversely, psychological richness could also predict subsequent self-compassion. This research provides new insights into the bidirectional relationship between self-compassion and psychological richness, broadening our understanding of the association between self-compassion and well-being. Future interventions should focus on the important effect of self-compassion interventions in the development of psychological richness. In addition, future research could consider interventions on increasing psychological richness to improve the level of self-compassion among college students.

15.
Ecol Appl ; : e3042, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39403722

RESUMO

Planting diverse forests has been proposed as a means to increase long-term carbon (C) sequestration while providing many co-benefits. Positive tree diversity-productivity relationships are well established, suggesting more diverse forests will lead to greater aboveground C sequestration. However, the effects of tree diversity on belowground C storage have the potential to either complement or offset aboveground gains, especially during early stages of afforestation when potential exists for large losses in soil C due to soil decomposition. Thus, experimental tests of the effects of planted tree biodiversity on changes in whole-ecosystem C balance are needed. Here, we present changes in above- and belowground C pools 6 years after the initiation of the Forests and Biodiversity experiment (FAB1), consisting of high-density plots of one, two, five, or 12 tree species planted in a common garden. The trees included a diverse range of native species, including both needle-leaf conifer and broadleaf angiosperm species, and both ectomycorrhizal and arbuscular mycorrhizal species. We quantified the effects of species richness, phylogenetic diversity, and functional diversity on aboveground woody C, as well as on mineral soil C accumulation, fine root C, and soil aggregation. Surprisingly, changes in aboveground woody C pools were uncorrelated to changes in mineral soil C pools, suggesting that variation in soil C accumulation was not driven by the quantity of plant litter inputs. Aboveground woody C accumulation was strongly driven by species and functional identity; however, plots with higher species richness and functional diversity accumulated more C in aboveground wood than expected based on monocultures. We also found weak but significant effects of tree species richness, identity, and mycorrhizal type on soil C accumulation. To assess the role of the microbial community in mediating these effects, we further compared changes in soil C pools to phospholipid fatty acid (PLFA) profiles. Soil C pools and accumulation were more strongly correlated with specific microbial clades than with total microbial biomass or plant diversity. Our results highlight rapidly emerging and microbially mediated effects of tree biodiversity on soil C storage in the early years of afforestation that are independent of gains in aboveground woody biomass.

16.
Front Insect Sci ; 4: 1385653, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39359692

RESUMO

Introduction: Cotton production in Tanzania is facing significant challenges due to insect pests that cause extensive damages to the crop. The most notable pests include the African bollworm (Heliothis armigera Hubner), Spiny bollworm (Earias biplaga Walker), Cotton stainers (Dysdercus sidae (Herrich-Schaeffer), Cotton Aphids (Aphis gossypii Glover), Thrips (Thrips tabaci Lindeman), Jassids (Amrasca biguttula, Bigutula), Leafhoppers (Cicadellidae jassidae), and Whiteflies (Bemisia tabaci Genn). If left uncontrolled, these pests can cause up to 60% damage to the crop. Despite the importance of cotton and the fact that most of these pests are endemic, there are scanty knowledge on the dynamics and distribution of cotton pests across the seasons of the year and crop's phenological growth stages (germination, vegetative growth, flowering and boll formation) in areas under repeated cultivation of the crop in Tanzania. Here we report on the influence of seasons and cotton's phenological stages on the abundance, diversity, distribution and richness of cotton insect pests. Methods: The study was conducted in the Misungwi district for two cotton-growing seasons, using the UKM08 cotton variety. Stick traps and handpicking methods were deployed in catching the cotton insect pests. Results: On average, a total of 8,500 insect specimen of diverse families and species were collected every season. The four dominant species among the collected were Aphis gossypii (17.37%), Amrasca biguttula (11.42%), Nezara viridura (10.7%), and Bemisia tabacci (10.68%). Both cotton phenological growth stages and seasons significantly (p<0.05) influenced the abundance, diversity, distribution and richness of cotton insect pests. In particular, the phenological growth stage 3 exhibited greater diversity of insect pests. The pests' distribution patterns remained relatively uniform across the crop growth stages. Discussion: Findings from the present study could contribute to developing sustainable pest management strategies in areas under repeated cotton production in Tanzania and elsewhere.

17.
Front Microbiol ; 15: 1434252, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39360315

RESUMO

We evaluated the effects of cottonseed meal protein hydrolysate (CPH) on the intestinal microbiota of yellow-feather broilers. We randomly divided 240 chicks into four groups with six replicates: basal diet with 0% (CON), 1% (LCPH), 3% (MCPH), or 5% (HCPH) CPH. The test lasted 63 days and included days 1-21, 22-42, and 43-63 phases. The ACE, Chao1, and Shannon indices in the MCPH and HCPH groups of 42-day-old broilers were higher than those in the CON group (p < 0.05), indicating that the cecum microbial diversity and richness were higher in these groups. Firmicutes and Bacteroidetes were the dominant phyla; however, the main genera varied during the different periods. The abundance of Lactobacillus in CPH treatment groups of 21-day-old broilers was high (p < 0.05); in the 42-day-old broilers, the abundances of Barnesiella, Clostridia_vadinBB60_group, and Parasutterella in the LCPH group, Desulfovibrio, Lactobacillus, Clostridia_vadinBB60_group, and Butyricicoccus in the MCPH group, and Megamonas and Streptococcus in the HCPH group increased; in the 63-day-old broilers, the abundance of Clostridia_UCG-014 and Synergistes in the LCPH and HCPH group, respectively, increased (p < 0.05), and that of Alistipes in the LCPH and MCPH groups decreased (p < 0.05). And changes in the abundance of probiotics were beneficial to improve the intestinal morphology and growth performance. In addition, the LCPH treatment increased the complexity of the microbial network, while the MCPH treatment had the same effect in 42-day-old broilers. Thus, CPH increased the relative abundance of beneficial intestinal microbiota and enhanced the richness and diversity of the bacterial microbiota in broilers aged <42 days; this effect was weakened after 42 days.

18.
Sci Rep ; 14(1): 24421, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39424913

RESUMO

Water richness evaluation of coal seam roofs is a crucial prerequisite for preventing and controlling water hazards in coal seam roofs. For this purpose, Spearman correlation and GeoDetector were employed for factor optimization to investigate the significance of lithological and structural factors and the impact of interactions among different factors on the water richness of coal seam roofs. Water richness evaluation models of coal seam roofs were separately established via the entropy weight method (EWM), coefficient of variation method (CVM), and random forest method (RFM), and the predictive accuracies of these models were compared. Eleven lithological and structural factors were collected. Through Spearman correlation analysis, 6 factors were identified to have significant influences on water richness. By utilizing the interaction detection of GeoDetector, the effects of interfactor interactions on water richness were explored, and 3 combination factors were selected. AICc was used to determine the model's superiority. The evaluation results of the study area based on factor optimization and three methods were further compared and validated via pumping tests, workface water inflow tests, and three-dimensional high-density electrical method. The results indicated that the RFM exhibited higher prediction accuracy than did the entropy weight and coefficient of variation methods. Additionally, within each method, factor optimization led to improved model accuracy.

19.
Sci China Life Sci ; 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39432205

RESUMO

Plant diversity significantly impacts ecosystem processes and functions, yet its influence on the community assembly of leaf fungi remains poorly understood. In this study, we investigated leaf epiphytic and endophytic fungal communities in a Chinese subtropical tree species richness experiment, ranging from 1 to 16 species, using amplicon sequencing to target the internal transcribed spacer 1 region of the rDNA. We found that the community assembly of epiphytic and endophytic fungi was predominantly governed by stochastic processes, with a higher contribution of dispersal limitation on epiphytic than on endophytic fungal communities but a higher contribution of selection on endophytic than on epiphytic fungal communities. The plant-epiphytic fungus interaction network was more complex (e.g., more highly connected and strongly nested but less specialized and modularized) than the plant-endophytic fungus interaction network. Additionally, tree species richness was positively correlated with the network complexity and diversity of epiphytic (α-, ß- and γ-diversity) and endophytic (ß- and γ-diversity) fungi, but was not associated with the contribution of the stochastic and deterministic processes on the community assembly of epiphytic and endophytic fungi. This study highlights that tree species diversity enhances the diversity and network complexity, rather than alters the ecological processes in community assembly of leaf-associated fungi.

20.
Ecol Evol ; 14(9): e70275, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39318531

RESUMO

Richness and evenness, two important components of diversity, have been the subject of numerous studies exploring their potential dependence or lack thereof. The results have been contradictory and inconclusive, but tending to indicate only a low (positive or negative) correlation. While such reported studies have been based on particular data sets and species abundance distributions, the present article provides the results of a study using randomly generated abundance distributions and hence more generalizable findings and valid statistical results. The results reveal no statistically significant correlation between richness and evenness based on such random sample of abundance distributions and on four well-known measures of diversity, including Simpson's indices and the entropy index. Of the two diversity components, evenness is found to have the strongest influence on diversity, but for numbers-equivalent or effective-number formulations, richness tends to be the most influential diversity component. For analyzing the tradeoff between richness and evenness for any given diversity measure and abundance distribution, the richness-evenness curve is introduced as a new tool for diversity analysis.

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