Role Of Abiotic Factors Research Articles

Variation in insect herbivory across an urbanization gradient: The role of abiotic factors and leaf secondary metabolites

Urbanization impacts plant-herbivore interactions, which are crucial for ecosystem functions such as carbon sequestration and nutrient cycling. While some studies have reported reductions in insect herbivory in urban areas (relative to rural or natural forests), this trend is not consistent and the underlying causes for such variation remain unclear. We conducted a continental-scale study on insect herbivory along urbanization gradients for three European tree species: Quercus robur, Tilia cordata, and Fraxinus excelsior, and further investigated their biotic and abiotic correlates to get at mechanisms. To this end, we quantified insect leaf herbivory and foliar secondary metabolites (phenolics, terpenoids, alkaloids) for 176 trees across eight European cities. Additionally, we collected data on microclimate (air temperature) and soil characteristics (pH, carbon, nutrients) to test for abiotic correlates of urbanization effects directly or indirectly (through changes in plant secondary chemistry) linked to herbivory. Our results showed that urbanization was negatively associated with herbivory for Q. robur and F. excelsior, but not for T. cordata. In addition, urbanization was positively associated with secondary metabolite concentrations, but only for Q. robur. Urbanization was positively associated with air temperature for Q. robur and F. excelsior, and negatively with soil nutrients (magnesium) in the case of F. excelsior, but these abiotic variables were not associated with herbivory. Contrary to expectations, we found no evidence for indirect effects of abiotic factors via plant defences on herbivory for either Q. robur or F. excelsior. Additional biotic or abiotic drivers must therefore be accounted for to explain observed urbanization gradients in herbivory and their interspecific variation.

Role of abiotic factors in the manifestation of <i>Bombyx mori</i> Nucleopolyhedrovirus

Role of abiotic factors in the manifestation of <i>Bombyx mori</i> Nucleopolyhedrovirus

Role of abiotic factors in the manifestation of <i>Bombyx mori</i> Nucleopolyhedroviru

Role of abiotic factors in the manifestation of <i>Bombyx mori</i> Nucleopolyhedroviru

Understanding the dynamic interactions of root-knot nematodes and their host: role of plant growth promoting bacteria and abiotic factors.

Root-knot nematodes (Meloidogyne spp., RKN) are among the most destructive endoparasitic nematodes worldwide, often leading to a reduction of crop growth and yield. Insights into the dynamics of host-RKN interactions, especially in varied biotic and abiotic environments, could be pivotal in devising novel RKN mitigation measures. Plant growth-promoting bacteria (PGPB) involves different plant growth-enhancing activities such as biofertilization, pathogen suppression, and induction of systemic resistance. We summarized the up-to-date knowledge on the role of PGPB and abiotic factors such as soil pH, texture, structure, moisture, etc. in modulating RKN-host interactions. RKN are directly or indirectly affected by different PGPB, abiotic factors interplay in the interactions, and host responses to RKN infection. We highlighted the tripartite (host-RKN-PGPB) phenomenon with respect to (i) PGPB direct and indirect effect on RKN-host interactions; (ii) host influence in the selection and enrichment of PGPB in the rhizosphere; (iii) how soil microbes enhance RKN parasitism; (iv) influence of host in RKN-PGPB interactions, and (v) the role of abiotic factors in modulating the tripartite interactions. Furthermore, we discussed how different agricultural practices alter the interactions. Finally, we emphasized the importance of incorporating the knowledge of tripartite interactions in the integrated RKN management strategies.

Artificial intelligence unveils key interactions between soil properties and climate factors on Boletus edulis and B. reticulatus mycelium in chestnut orchards of different ages

The main objective of this study was to determine the possible interaction of two important abiotic factors (soil and climate) on the mycelial concentration and frequency of the ectomycorrhizal fungi Boletus edulis and B. reticulatus, using traditional statistics and artificial neural network tools. The frequency and concentration of Boletus mycelium were determined over three months (September, October, and November), and two years (2018 and 2020), in three hybrid chestnuts (Castanea × coudercii) orchards of 40-, 10-, and 3- years-old, using real-time qPCR. Statistical analysis revealed a significant effect of the year on B. edulis mycelium concentration and of the sampling plot (different tree ages) on B. reticulatus frequency. The combination of artificial intelligence networks (ANN) with fuzzy logic, named neurofuzzy logic (NF), allowed the construction of two robust models. In the first, using year, month, and sampling plot as inputs, NF identified hidden interactions between year and month on B. edulis mycelium concentration and between sampling plot and sampling month on B. reticulatus mycelium frequency, thus improving the information obtained from the statistical analysis. In the second model, those three factors were disaggregated into 44 inputs, including 20 soil properties and 24 climatic factors, being NF able to select only 8 as critical factors to explain the variability found in both ectomycorrhizal Boletus species regarding mycelial frequency and concentration. Specifically, NF selected two chemical soil properties (cation exchange capacity and total carbon) and three physical properties (macroaggregates, total porosity, and soil moisture at field capacity), as well as their interactions with three climatic elements (cumulative difference between precipitation and potential evapotranspiration (P-PET-1-2) and water deficit (WD-1-2) in the previous two months and excess water (WE-1) in the month prior to sampling. These results provide a much deeper understanding and new insights into the ecology and the role of abiotic factors which explain the different mycelial development patterns of ectomycorrhizal fungi such as B. edulis and B. reticulatus in chestnut agroecosystems.

Temperature dissimilarity drives flower–visitor interaction turnover across elevation in the Mexican Transition Zone

AbstractAimMost biodiversity studies have considered species to be isolated entities, neglecting the fact that their biotic interactions and spatial variation are fundamental to their persistence across elevational gradients. Here, using a standardized sampling methodology, we evaluated how and why the composition of flower–visitor interactions (i.e. beta diversity) varies over an extensive elevational gradient. Specifically, we aimed to identify which biotic (species turnover) and abiotic factors (temperature, precipitation and primary productivity) inherent to elevational gradients can explain the distribution of floral visitor–plant interactions.LocationMexican Transition Zone.TaxonAngiosperms, Hymenoptera, Lepidoptera, Diptera, Hemiptera and Coleoptera.MethodsWe sampled ecological interactions between floral visitors and flowering plants at 10 sites along an elevational gradient from 4 to 3425 m.a.s.l. We measured the additive partitioning of the beta diversity of species interactions and used generalized dissimilarity modelling to assess how spatial and environmental factors can explain the observed dissimilarity.ResultsWe found that the composition of interactions between floral visitors and plant species differs from lowlands to highlands mainly due to differences in temperature across the studied elevation gradient, rather than geographical distance or other environmental factors (i.e. mean annual precipitation and net primary productivity). We also observed that the main component of the beta diversity of interactions was interaction turnover driven by the turnover of both plants and floral visitors along the elevation gradient studied, which may be influenced by both temperature and the biogeographical affinity of biotas.Main ConclusionsWe conclude that environmental filters play a crucial role in the establishment of novel interactions, as temperature can filter species and impact the behaviour and traits of floral visitors and plants across an elevational gradient. These findings underscore the importance of considering the role of abiotic factors in predicting and explaining the distribution of species interactions across different elevational gradients.

AMONG-SPECIES VARIATION IN FLOWER SIZE DETERMINES FLORIVORY IN THE LARGEST SEASONALLY FLOODED TROPICAL WETLAND.

Floral damage caused by florivores often has negative consequences for plant reproduction. However, the factors affecting plant-florivore interactions are still poorly understood, especially the role of abiotic factors and interspecific variation in florivory within ecosystems. Thus, it is largely required to investigate the patterns of florivory levels and its consequences for plant communities. We assessed the influence of abiotic factors related to climatic seasonality, of phylogenetic relationships among plants, and of functional attributes associated with attractiveness to pollinators on florivory levels (incidence and intensity) in the Pantanal, the world's largest tropical wetland. Between December 2020 and November 2021, the percentage of both flowers attacked (incidence) and area removed from petals (intensity) by florivores were examined in 51 species from 25 families, considering flowering season, the substrate where the plants occur, and floral attributes as potentially determining factors on florivory levels. Phylogeny and environmental factors did not have a significant influence on florivory. The only determinant of interspecific variation in florivory incidence and intensity was flower size, where larger flowers experienced higher florivory levels regardless of season and substrate, while flower arrangement and color were not significant factors. Our study is one of the first to estimate the community-wide effects of biotic and abiotic factors on both the incidence and the intensity of florivory. The magnitude of this plant-florivore interaction may reduce reproductive success and entail selective pressures on plant attractiveness to pollinators. This article is protected by copyright. All rights reserved.

Mollusk Thanatocoenoses Unravel the Diversity of Heterogeneous Rhodolith Beds (Italy, Tyrrhenian Sea)

Emerging evidence of rhodolith bed complexity and heterogeneity poses a challenge to monitoring strategies and questions about the role of abiotic factors in controlling the observed morphostructural diversity. Mollusk thanatocoenoses quickly respond to environmental conditions, expressing fidelity to biocoenosis and representing, thus, a useful ecological/paleoecological tool to unravel this heterogeneity. In this research, we studied three distinct rhodolith beds from the Tyrrhenian Sea (Italy), in a range between 40 and 100 m of water depth, together with their mollusk thanatocoenoses, sediment size, and oceanographic conditions. The beds are all heterogeneous and rarely correspond to a specific rhodolith morphotype and shape. On the contrary, the study of the associated thanatocoenoses led to distinguish at least five different assemblages within the known variability of the Coastal detritic (DC) association. DC and deep mud (VP) mollusk species dominate hanatocoenosis A, which is associated with mixed sediment and a low hydrodynamic regime. Thanatocoenosis B corresponds to an assemblage in which DC species mixed with species of adjacent vegetated bottoms in sandy sediment with a medium hydrodynamic. Thanatocoenosis C includes species related to muddy coastal detritic (DE) and offshore detritic (DL) associated with sand and a variable proportion of praline and branch morphotypes. Thanatocoenoses D and E include a wide range of detritic species (DE DC, DL) together with VP and coralligenous (C), associated with exclusive praline and gravelly sand (Thanat. D), or a mixed proportion of branch and praline and mixed sediment (Thanat. E). Our results demonstrate that the study of mollusk thanatocoenoses provides insights into the diversity within and among heterogeneous rhodolith beds. Moreover, rhodoliths, as part of the sediment, create microhabitats suitable for a wide range of mollusk species that contribute to the formation of complex thanatocoenoses.

First Maximum Sustainable Yield advice for the Nephrops norvegicus stocks of the Northwest Iberian coast using stochastic Surplus Production model in Continuous Time (SPiCT)

The assessment of the status of fisheries resources is pivotal due to the importance of marine resources in global food security and to halt the ongoing decline in marine biodiversity. Norway lobster (Nephrops norvegicus) is one of the most valuable resources in the Northeast Atlantic. However, overfishing has caused the decline of several Nephrops stocks over the last decades, particularly in the Nephrops Functional Units (FUs) 25 (NW Spain), 26-27 (NW Spain and North Portugal) and 31 (Cantabrian Sea, North Spain). Since 2003, the information provided by the very low level of landings and fishing effort of these three stocks was insufficient to carry out an adequate analytical assessment, so the base of the assessment has been the trends from commercial catch per unit effort (CPUE). The objective of this study was to carry out the first assessment of these three stocks with an analytical MSY-based model. A review of the available data was made and the stochastic Surplus Production Model in Continuous Time (SPiCT) was fitted for each FU. The results indicate an extremely low biomass for FUs 25 and 26-27 since the mid-nineties well below the reference points. For FU 31, on the other hand, estimated biomass is larger. Our findings also identified long-term temporal and spatial changes in the population dynamic of Nephrops in the Northwest Iberian coast. The results were compare with those obtained in the same stocks with other data-limited methods. Also the role of abiotic factors on the observed dynamic of the stocks was explored. The results of this study are not only relevant for the sustainable exploitation of Norway lobster stocks off the Northwest Iberian coast but provide valuable insights into the suitability and limitations of production models for the assessment of crustacean stocks in general.

CRITERIA FOR ASSESSMENT OF ENVIRONMENTAL RISKS IN AGROCENOSES UNDER THE INFLUENCE OF ABIOTIC FACTORS

The study of environmental risks in the agricultural industry in the conditions of global climate change remains relevant. The role of abiotic factors (air temperature and precipitation) in the formation of environmental risks in agrocenoses of agricultural crops is covered in the article. The influence of uncontrolled fluctuations of agroclimatic factors on agrocenoses, which cause environmental risks, is particularly hazardous. They are the main prerequisite for reducing the efficiency of agriculture. The aim of the work was to develop and substantiate the criteria for evaluating ecological risks in agrocenoses under the influence of abiotic agroclimatic factors in the conditions of climate change. The defined criteria provide an assessment of the ecological risks of loss of fertility and reduction of soil quality, deterioration of the phytosanitary condition of agrocenoses, and reduction of their productivity. Such criteria include indicators of the content of organic matter and the coefficient of soil dehumification, which indicate a decrease in the share of organic matter in the soil; agrochemical indicators that confirm the risks of loss of macro- and microelements, changes in soil pH; normative indicators of the content of pollutants, which determine the level of ecological risks of soil contamination with dangerous compounds of heavy metals, pesticides and radionuclides. The criteria that determine the phytosanitary state of agrocenoses, determine the indicators of weediness, plant diseases that lead to death or thinning, an increase in the number of species of harmful organisms, and an approximate economic threshold of the harmfulness of pests. It characterizes the degree of damage to crops and possible crop losses. Ecological risks of agrocenoses productivity loss are determined by criteria for assessing crop loss from major diseases and indicators of quality and safety of agricultural products. The use of the specified criteria will ensure the timely elimination of the environmental risks outlined in the article thanks to the implementation of appropriate agrotechnical preventive and protective measures, will guarantee the growth of the productivity of agrocenoses and the ecological safety of agroecosystems.

Role of abiotic factors in enhancing the capacity of mangroves in reducing ocean acidification.

The present study investigated the effects of rising carbon dioxide levels in nature and the carbon sequestration potential of dominant mangrove species for reducing the toxic effects of ocean acidification. The study was conducted on the east coast of Odisha, in the western Bay of Bengal. To determine the effect of these ambient parameters on the absorption of carbon dioxide by the mangroves, water temperature, salinity, pH levels of seawater along with soil texture and pH, salinity expressed in electrical conductivity, compactness expressed in bulk density, and soil organic carbon were simultaneously monitored. The aboveground biomass and carbon of the selected species were studied for 2 consecutive years at 10 designated stations. The total carbon calculated for the study area varied from 242.50 ± 49.00 to 1321.29 ± 445.52 tons with a mean of 626.68 ± 174.81 tons for Bhitarkanika and Mahanadi mangrove chunks. This is equivalent to 2299.92 ± 641.55 tons of CO2 absorbed from the atmosphere. A total of 27 equations were selected as the best fit models for the study area. The equations between mangrove biomass and carbon along with aquatic and edaphic factors governing the pH of water and soil strongly support the positive influence of mangrove photosynthetic activity in shifting the equilibrium toward alkalinity. This calls for conservation of mangrove ecosystem to minimize the pace of acidification of estuarine water. The results indicate that Excoecariaagallocha and Avicennia marina as are the most capable species for combatting maximum carbon dioxide toxicity from the atmosphere; which will be helpful in REDD + programs and carbon-based payments for ecosystem services (PES).

Context-dependent role of abiotic and biotic factors structuring nematode communities along two environmental gradients.

Although abiotic environmental factors have been historically regarded as the dominant deterministic process in microbial community assembly, recent studies indicate that biotic interactions may be equally significant. However, the extent to which both processes are important in assembly of belowground communities is unknown. Along two environmental gradients: alkalinity (ranging from pH ~7 to ~11) and habitat type (lakes, shorelines, and prairies around lakes) present in the Western Nebraska Sandhills, we used 18S rRNA gene marker metabarcoding and statistical analyses, including generalized dissimilarity modelling (GDM), to evaluate the dynamics between abiotic and biotic factors that might play a role in nematode community assembly. Lakes supported the least diverse and prairies the most diverse communities with completely distinct compositions. We also observed a potential role of alkalinity in shaping these communities but only in lakes. Generally, GDMs indicated the influence of both abiotic and biotic factors. However, their relative importance in explaining community variability was dependent on the habitat. Biotic factors influenced the lake communities most, followed by shorelines and prairies, explaining ~47%, 27% and 8% of the variation, respectively. In contrast, the role of abiotic factors was relatively similar in lakes, shorelines and prairies (~15%, 18% and 14% of the variation, respectively). Most variation in the shorelines (62%) and prairies (82%) remained unexplained, suggesting the potential importance of factors associated with specific traits or a stronger role of stochastic processes. Nevertheless, our findings suggest both deterministic processes are important in nematode community assembly, but their specific contributions are context-dependent.

Phytoplankton Diversity of a Demineralized Urban Wetland of Meghalaya State of Northeast India: The Spatio-temporal Variations and the Role of Abiotic Factors

The authors analyze phytoplankton diversity of a small urban wetland of Meghalaya to assess biodiversity and limnology interest of small water bodies. This “slightly acidic-circumneutral, demineralized and soft water” subtropical wetland reveals diverse phytoplankton (64 species), indicates high desmid richness and highlights the speciose littoral constellations of up to 55-58 species per sample. Phytoplankton comprises dominant quantitative component of net plankton and registers Charophyta dominance; Chlorophyta > Bacillariophyta > Dinozoa > Chrysophyta > Cyanobacteria depict sub-dominance, and Euglenozoa and Cryptophyta show poor abundance at the littoral and semi-limnetic regions. The richness of phytoplankton and abundance of phytoplankton, Charophyta, Chlorophyta, Dinozoa, Chrysophyta and Cyanobacteria follow bimodal spatio-temporal variations. Closterium, Cosmarium, Staurastrum, Micrasterias, Netrium, Staurodesmus and Scenedesmus are notable genera, and 14 species collectively influence phytoplankton abundance. Phytoplankton registers high species diversity, lower dominance and high evenness. Amongst 15 abiotic factors, only the rainfall and sulphate exert notable influence individually, while the canonical correspondence analysis registers lower cumulative influence of the selected 10 factors on the littoral and semi-limnetic phytoplankton assemblages. This study merits interest for neglected biodiversity and ecology of small aquatic biotopes of India and urban wetlands in particular.

Role of abiotic factors on the seasonal variation in infestation of the major insect pests of rice (Oryza sativa L.) in Odisha

Role of abiotic factors on the seasonal variation in infestation of the major insect pests of rice (Oryza sativa L.) in Odisha

Role of Abiotic Factors on House Dust Mite Population: Control and Allergen Avoidance - A Review Article

House dust mites (HDM’s) are an important source of indoor allergens in the house dust and cause various kinds of allergies. They are strongly influenced by abiotic factors such as temperature, relative humidity and seasonal variations. HDM’s are present in houses all over the year but their number varies in different seasons and habitats. The moderate environmental temperature, high relative humidity and adequate food sources are the key factors for their proliferation. The season has a great effect on the mite population. In the rainy season, moderate temperature and high relative humidity are the favorable conditions for the growth of mites, and the population of mites reaches a peak level. Whereas, high temperature and low relative humidity during summer season significantly reduce the mite population level and in the winter season, fall in temperature will drastically reduce the mite number because mites perish due to chilling. Relative humidity of a particular place plays an important role in the growth of mites. By controlling the relative humidity of a particular place, the HDM allergens can be reduced in that place. The prevalence of these mites and their allergen content vary within the locations in the home. Mattresses, carpets, sofas are the main reservoir of HDM’s, as the dust and shed skin scales accumulate in these places and provide abundant nutrition to dust mites. To reduce the allergen content from houses, frequent cleaning and vacuuming of mattresses and pillows, the use of encasement should be advised for allergic subjects.

Elevation gradient distribution of indices of tree population in a montane forest: The role of leaf traits and the environment

To disentangle the controls on species distribution in the context of climate change is a central element in proposed strategies to maintain species diversity. However, previous studies have focused mainly on the roles of abiotic factors (e.g., climate and soil properties), with much less attention given to the roles of biotic factors such as functional traits. Here, we measured eight leaf traits for 240 individual trees of 53 species and analyzed the variation in traits and population composition indices and their relationships with soil properties, climate factors, and leaf traits. The tree density, frequency and species importance values of the overall species and saplings significantly increased with increasing elevation, while the same indices (except for species frequency) of adults did not significantly change. The largest percentage of variation of species importance value (greater than 50%) was explained by climate, but leaf traits played a critical role in driving elevation distribution patterns of both saplings and adults; the abundance of saplings significantly increased with elevation, with increased leaf carbon contents, while the abundance of adults did not change in accordance with a nutrient conservation strategy associated with the leaf economic spectrum. Our results suggest that the elevation gradient distribution of woody plant species is dependent on tree size and that local atmospheric humidity and leaf traits cause considerable variation in species distribution along subtropical mountain elevations. We provide evidence of which leaf traits play a key role in the elevation gradient distribution of different sizes of woody tree species.

Incorporating thermodynamics in predator-prey games predicts the diel foraging patterns of poikilothermic predators.

Models of foraging behaviour typically assume that prey do not adapt to temporal variation in predation risk, such as by avoiding foraging at certain times of the day. When this behavioural plasticity is considered-such as in predator-prey games-the role of abiotic factors is usually ignored. An abiotic factor that exerts strong influence on the physiology and behaviour of many animals is ambient temperature, although it is often ignored from game models as it is implicitly assumed that both predators and prey are homothermic. However, poikilotherms' performance may be reduced in cold conditions due to reduced muscle function, limiting the prey-capture ability of predators and the predator-avoidance and foraging abilities of prey. Here, we use a game-theoretic predator-prey model in which diel temperature changes influence foraging gains and costs to predict the evolutionarily stable diel activity of predators. Our model predicts the range of patterns observed in nature, including nocturnal, diurnal, crepuscular and a previously unexplained post-sunset crepuscular pattern observed in some sharks. In general, smaller predators are predicted to be more diurnal than larger ones. The safety of prey when not foraging is critical, explaining why predators in coral reef systems (with safe refuges) may often have different foraging patterns to pelagic predators. We make a range of testable predictions that will enable the further evaluation of this theoretical framework for understanding diel foraging patterns in poikilotherms.

Shared patterns in body size declines among crinoids during the Palaeozoic extinction events

Crinoids were among the most abundant marine benthic animals throughout the Palaeozoic, but their body size evolution has received little attention. Here, we compiled a comprehensive database on crinoid calyx biovolumes throughout the Palaeozoic. A model comparison approach revealed contrasting and complex patterns in body size dynamics between the two major crinoid clades (Camerata and Pentacrinoidea). Interestingly, two major drops in mean body size at around two mass extinction events (during the late Ordovician and the late Devonian respectively) are observed, which is reminiscent of current patterns of shrinking body size of a wide range of organisms as a result of climate change. The context of some trends (marked declines during extinctions) suggests the cardinal role of abiotic factors (dramatic climate change associated with extinctions) on crinoid body size evolution; however, other patterns (two intervals with either relative stability or steady size increase in periods between mass extinctions) are more consistent with biotic drivers.

Role of abiotic factors and habitat heterogeneity in the interactions between stream salamanders and crayfish in the southern Appalachians

AbstractSpecies interactions are important for determining the biological organization of natural communities. Presumably, as interacting organisms become more similar in resource niches, the magni...

Establishment of Cryptostegia madagascariensis in the semiarid: what is the role of abiotic factors in germination and initial growth?

Studies on seed germination and seedling development in different environmental conditions help to understand the ability of exotic species to colonize new environments. Cryptostegia madagascariensis is an exotic invasive species in the semiarid Caatinga Phytogeographical Domain, in the northeastern region of Brazil. In this study, was evaluate how the abiotic factors interfere in germination and the impacts of a water deficit in the initial growth of seedlings. During germination, the seeds were exposed to different temperatures (constant and alternating) combined with two light conditions (white and dark light). In germination, we also evaluated the effects of water and saline stress. In initial growth, the seedlings were submitted to four levels of water availability (100%, 70%, 40% and 10% of field capacity). The milder (20 at 30°C) and alternate temperatures studied provided greater germination four days after sowing, independent of light. High temperatures (35°C) are a limiting factor for germination, as well as water and saline stress (>2 MPa). The water deficit reduces the growth of the seedlings, but these showed morphological adaptations to the different treatments. However, lower levels of water reduced its invading potential. Therefore, factors such as high temperature (> 30° C), saline and water stress, reduce its germination potential and the reduction of water availability affects its growth, but not its survival.