Critical Limits Research Articles

Short-term effects of compaction on soil mechanical properties and pore functions of an Andisol

Several studies on soil physical quality have related soil structural properties to bulk density, proposing values for critical limits in relation to the soil compaction status. However, these values are not applicable to Andosols due to their very low bulk density (< 0.9 Mg m−3). This work aimed to evaluate the short-term effects of soil compaction on the soil physical quality of an Andosol. The experiment was established in May 2019. Soil cores were collected from the soil surface and field measurements (penetration resistance, volumetric water content and air conductivity) were conducted to monitor changes in the soil physical quality after compaction events. The soil was compacted using rollers (weighing between 1.20 and 1.37 Mg) to reach three bulk densities (T0: 0.65, T1: 0.75 and T2: 0.85 Mg m−3) by controlling the number of roller passes. Soil compaction induced an increase in the soil bulk density that resulted in an increase in the mechanical strength (e.g. maps of penetration resistance revealed values from (T0) 500 kPa to (T2) 1500 kPa) and caused a decrease in the volume of macropores (e.g. air capacity in T0 and T2 was 22% and 11%, respectively) responsible for water infiltration and flow. The latter provoked an increase in the volumetric water content in the upper 10 cm of the soil, which decreased the field air conductivity due to the reduced pore space and its continuity. Bulk density also increased due to wetting and drying cycles, showing the effect of the natural rearrangement of soil particles, which was more intense in the soil with the lowest bulk density. When the bulk density of the tilled soil increased to values over 0.80 Mg m−3, soil pore functions related to soil aeration reached critical values (air capacity < 10% and air permeability < 1 µm2) concerning soil compaction, while the soil precompression stress (around 60 kPa) and plant available water (> 20%) remained within an optimal range.

Uncertainties in Spatial Orientation: Critical Limits for Landmark Inaccuracies in Maps in the Context of Map Matching

Map information, especially volunteered geographic information (VGI) is prone to spatial inaccuracies. Due to their use as spatial reference points, spatially inaccurate landmark representations in maps might affect the ability to match maps to the represented 3D space and might compromise self-localization and orientation. Based on a map matching task in a virtual 3D environment and various degrees of spatial landmark inaccuracies in a simultaneously presented 2D map, we aimed to identify acceptable and critical values of spatial inaccuracies. Furthermore, potential effects of inaccurate semantic spatial categories were evaluated. The findings demonstrate how metric and semantic spatial inaccuracies of landmark representations affect matching of maps to the represented 3D space. Map inaccuracies corresponding to more than 10 m within 3D space and swapped landmark pictograms in a map were associated with the perception of a mismatch between maps and 3D spaces. Furthermore, the distance of landmarks to the perceiver was found to affect map matching. Spatial inaccuracies of landmark pictograms were less likely to be associated with a perceived mismatch between maps and 3D spaces when the landmarks were further away, presumably because small or moderate inaccuracies were more difficult to perceive. To reduce the identified effects of landmark inaccuracies in maps on map-matching performance, we propose to identify means to quantify the uncertainty concerning spatial landmark inaccuracies and to visually communicate this uncertainty to map users.

EFFECT OF INTEGRATED NUTRIENT MANAGEMENT ON SYMBIOTIC EFFICIENCY AND SOIL FERTILITY UNDER GREEN GRAM [VIGNA RADIATA (L.) WILCZEK] CULTIVATION

A field experiment was conducted at Instructional Farm (Agronomy), RCA, Udaipur, (Rajasthan) during Kharif, 2014 on clay loam soil to study the effect of integrated nutrient management on symbiotic efficiency and fertility status of post-harvest soil under Green gram cultivation. The experiment was laid out according to a factorial randomized block design with three replications. The experiment comprised four fertility levels (75% RDF, 75% RDF+VC @ 2 t ha-1, 100% RDF and 100% RDF+VC @ 2 t ha-1) and four biofertilizers levels (control, Rhizobium, PSB and Rhizobium + PSB). The RDF was 20 kg N and 40 kg P2O5 per hectare. The soil of the experimental site was clay loam in texture, slightly alkaline in reaction, medium in available nitrogen and phosphorus, while high in potassium and DTPA extractable micronutrients sufficiently above the critical limits. The application of fertility level significantly increased the number of total and effective root nodules, fresh and dry weight of root nodules and leg haemoglobin content in root nodules upto 75% RDF+VC @ 2 t ha-1 however, their further increase with application of 100% RDF+VC @ 2 t ha-1 was found non-significant. Seed inoculation with Rhizobium + PSB significantly increased the number of total and effective root nodules, fresh and dry weight of root nodules and leg haemoglobin content in root nodules. The organic carbon, available nitrogen, phosphorus, potassium, copper, zinc, iron and manganese in soil significantly increased with inoculation of Rhizobium + PSB at the harvest stage of the crop, but EC and pH remain non-significant.

Analysis of heat and cold tolerance of a freeze-tolerant soil invertebrate distributed from temperate to Arctic regions: evidence of selection for extreme cold tolerance.

Tolerance to thermal extremes is critical for the geographic distributions of ectotherm species, many of which are probably going to be modified by future climatic changes. To predict species distributions it is important to understand the potential of species to adapt to changing thermal conditions. Here, we tested whether the thermal tolerance traits of a common freeze-tolerant potworm were correlated with climatic conditions and if adaptation to extreme cold constrains the evolutionary potential for high temperature tolerance. Further, we tested if evolution of thermal tolerance traits is associated with costs in other fitness traits (body size and reproduction). Lastly, we tested if slopes of temperature-survival curves (i.e., the sensitivity distribution) are related to tolerance itself. Using 24 populations of the potworm, Enchytraeus albidus Henle (Enchytraeidae), collected from a wide range of climatic conditions, we established a common garden experiment in which we determined high and low temperature tolerance (using survival as endpoint), average reproductive output and adult body size. Heat tolerance was not related to environmental temperatures whereas lower lethal temperature was about 10°C lower in Arctic populations than in populations from temperate regions. Reproduction was not related to environmental temperature, but was negatively correlated with cold tolerance. One explanation for the trade-off between cold tolerance and reproduction could be that the more cold-hardy populations need to channel energy to large glycogen reserves at the expense of less energy expenditure for reproduction. Adult body size was negatively related to environmental temperature. Finally, the slopes of temperature-survival curves were significantly correlated with critical temperature limits for heat and cold tolerance; i.e., slopes increased with thermal tolerance. Our results suggest that relatively heat-sensitive populations possess genetic variation, leaving room for improved heat tolerance through evolutionary processes, which may alleviate the effects of a warmer future climate in the Arctic. On the other hand, we observed relatively narrow sensitivity distributions (i.e., less variation) in the most heat tolerant populations. Taken together, our results suggest that both cold and heat tolerance can only be selected for (and improved) until a certain limit has been reached.

The use of contaminated soil and lithium slag for the production of sustainable lightweight aggregate

The contaminated soil (CS) and lithium slag (LS) contain amounts of hazardous ingredients which may move into the ground water and local cropland. In order to prevent CS and LS from damaging the environment, an investigation on the utilization of CS and LS for the production of lightweight aggregate (LWA) was presented in this article. The basic properties of LWA were evaluated. Furthermore, the crystalline phases of the produced LWA were analyzed, and the microstructure of LWA was analyzed by X-ray micro-tomography. The experimental results showed that the LWA produced from the CS and LS had good performances with density of 0.5–1.5 g/cm3 and compressive strength of 1.0–8.7 MPa, which met the required standard of LWA. Meanwhile, it can be revealed that the LS can reduce the sintering temperature of LWA, thus exhibiting low energy consumption. The analysis of crystal phases indicated that the mineral compositions of LWA contained spinel phases, which provided a possibility for the solidification of heavy metals. In addition, the evaluation of environmental effect revealed the leaching concentrations of hazardous metals were much lower than the critical limits of nonhazardous materials. Finally, the economic benefits were analyzed in the entire production process of LWA, which indicated that using CS and LS to produce LWA can lower the raw material cost by 85–98%. This work will create a more eco-friendly and economical method for the management of solid wastes (CS and LS). Meanwhile, this study can provide theoretical basis for the sustainable production of LWA.

Implementation of HACCP Management System in a Cake Manufacturing Company in Dhaka, Bangladesh: A Case Study

The study aims to provide technical information on the development and application of hazard analysis and critical control points (HACCP) in one of the popular cake manufacturing companies in Dhaka, Bangladesh. A generic HACCP plan in accordance with legal requirements was created after a detailed analysis of data collected from the company. Every step of the production process was examined for biological, chemical, and physical hazards. The prerequisite program was designed to address some hazards prior to production, thereby simplifying the HACCP plan. The critical control points were determined by answering the questions in the decision trees. Finally, the HACCP control chart was created to include critical limits, monitoring, and corrective actions as the components of several HACCP principles. One critical control point (CCP) and two operational prerequisite programs (oPRPs) were identified throughout the manufacturing process. This is the first HACCP study aimed at a cake manufacturing company, and it is expected that it would assist process engineers and quality control specialists in designing and implementing control measures.

Critical Limits for Soybean and Black Bean Root Growth, Based on Macroporosity and Penetrability, for Soils with Distinct Texture and Management Systems

Soil compaction is a worldwide problem in agricultural areas, and it is important to define soil properties and reference values that allow knowledge of the compaction level for decision making. The objective of this study was to define the critical values of physical properties associated with the compaction of soils. Three Ultisols and two Oxisols, under different management systems, were collected at different depths for an evaluation of particle size, volumetric moisture, bulk density, and porosity. In the field, soil resistance to penetration and the root length of the soybean and edible black bean crop were measured. The soil profiles presented horizontal layers with similar resistance, but in some cases, there is discontinuity of these layers, which allows the roots to use the zones of lower resistance to deepen in the profile. The values of bulk density and resistance to penetration critical to soybean and edible black bean (only in sandy loam soil) root growth, according to soil textural class, are: sandy loam = 1.66 Mg m−3 and 1.5 to 2 MPa; loam and clay loam = 1.52 Mg m−3 and 1 to 1.5 MPa; silty clay loam and silty clay = 1.32 Mg m−3 and 1.5 to 2 MPa; and clay = 1.33 to 1.36 Mg m−3 and 2 to 3.5 MPa.

Thermal tolerance and acclimation capacity in the European common frog (Rana temporaria) change throughout ontogeny.

Phenotypic plasticity may allow ectotherms with complex life histories such as amphibians to cope with climate-driven changes in their environment. Plasticity in thermal tolerance (i.e., shifts of thermal limits via acclimation to higher temperatures) has been proposed as a mechanism to cope with warming and extreme thermal events. However, thermal tolerance and, hence, acclimation capacity, is known to vary with life stage. Using the common frog (Rana temporaria) as a model species, we measured the capacity to adjust lower (CTmin ) and upper (CTmax ) critical thermal limits at different acclimation temperatures. We calculated the acclimation response ratio as a metric to assess the stage-specific acclimation capacity at each of seven consecutive ontogenetic stages and tested whether acclimation capacity was influenced by body mass and/or age. We further examined how acclimation temperature, body mass, age, and ontogenetic stage influenced CTmin and CTmax . In the temperate population of R. temporaria that we studied, thermal tolerance and acclimation capacity were affected by the ontogenetic stage. However, acclimation capacity at both thermal limits was well below 100% at all life stages tested. The lowest and highest acclimation capacity in thermal limits was observed in young and late larvae, respectively. The relatively low acclimation capacity of young larvae highlights a clear risk of amphibian populations to ongoing climate change. Ignoring stage-specific differences in thermal physiology may drastically underestimate the climate vulnerability of species, which will hamper successful conservation actions.

Effects of Modified Atmosphere Packaging, Storage Temperature, and Absorbent Pads on the Quality of Fresh Cape Hake Fish Fillets

This study investigated the effects of modified atmosphere packaging (MAP), storage temperature, and the use of absorbent pads (PAD) on the quality attributes of Cape hake (Merluccius capensis) fish fillets. Fresh Cape hake fillets were packaged under active-MA (40% CO2 + 30% O2 + 30% N2) or passive-MA (0.039% CO2 + 20.95% O2 + 78% N2), with and without PAD, and stored at 0 °C, 4 °C, and 8 °C (to mimic abuse temperature). The control fresh fillets were stored under passive-MAP without PAD at 0 °C, 4 °C, and 8 °C. Headspace O2 gas composition continuously decreased below critical limits under passive-MAP, with an increase in storage temperature. Similarly, O2 levels decreased under active-MAP but did not reach critical levels, with the lowest being 9.5% at 0 °C. The interaction of storage temperature and modified atmosphere had a significant effect on quality attributes of Cape hake fillets. Drip loss was higher in active-MAP packaged fillets without PAD (0.64%) than passive-MAP packaged fillets without PAD (0.27%). Drip loss was significantly reduced when using absorbent pads (p &lt; 0.05). Firmness, color, and pH were better maintained under active-MAP at the lowest temperature of 0 °C. Firmness (work of shear) of active-MA packaged fillets on day 12 at 0 °C and 4 °C was 527 N/s and 506 N/s, respectively. Fillets packaged under active-MAP at 0 °C had longer shelf-life than control passive-MAP fillets.

Critical thermal limits in ants and their implications under climate change.

Critical thermal limits (CTLs) constrain the performance of organisms, shaping their abundance, current distributions, and future distributions. Consequently, CTLs may also determine the quality of ecosystem services as well as organismal and ecosystem vulnerability to climate change. As some of the most ubiquitous animals in terrestrial ecosystems, ants are important members of ecological communities. In recent years, an increasing body of research has explored ant physiological thermal limits. However, these CTL data tend to centre on a few species and biogeographical regions. To encourage an expansion of perspectives, we herein review the factors that determine ant CTLs and examine their effects on present and future species distributions and ecosystem processes. Special emphasis is placed on the implications of CTLs for safeguarding ant diversity and ant-mediated ecosystem services in the future. First, we compile, quantify, and categorise studies on ant CTLs based on study taxon, biogeographical region, methodology, and study question. Second, we use this comprehensive database to analyse the abiotic and biotic factors shaping ant CTLs. Our results highlight how CTLs may affect future distribution patterns and ecological performance in ants. Additionally, we identify the greatest remaining gaps in knowledge and create a research roadmap to promote rapid advances in this field of study.

Fish stock assessment and potential yield of a reservoir in Benin City, Nigeria

Fish stock assessments of aquatic ecosystems are relevant against the backdrop of over exploitation, fish species extinction and the inadequate management of aquatic resources especially in developing countries such as Nigeria. The study specifically examined the fish stock assessment and the potential fish yield of the Ikpoba reservoir in Benin City, Nigeria. A total of 903 fishes were captured from the reservoir with individual abundance ranging from 18 (1.99 %) for Epiplatys sexfasciatus to 286 (31.67 %) for Synodontis clarias. A total of 15 fish species belonging to 8 families were identified while the dominant fish species were S. clarias, Hemichromis fasciatus and Marcusenius psittacus. A total of 11 fish species were identified as rare in this study. The Ekiuwa station of the reservoir was the richest species-wise (d= 6.45) while the Midpoint station had the greatest general diversity of fish species (H= 1.42). There was a more even spread and distribution of fish species at the Midpoint station (E= 1.00) while the commonest fish species were most frequent at the Okhoro station (C= 1.62). In this study, the Condition Factor ranged from 1.00 for M. psittacus to 5.78 for Gnathonemus abadii. The potential fish yield index of the reservoir was low due to a low nutrient content and ranged from 17.7 in the dry months to 23.13 in the wet months. It was advocated that the Ikpoba reservoir must be continuously monitored in order to ensure that fish species composition and diversity do not reach critical limits.

Reduction of lubricant life in lubrication systems for internal combustion engines due to high lubricant supply rates

The lubrication systems of internal combustion engines are not designed to avoid excessive oil consumption; therefore, the oil supply rate to the interior of the engine falls between two critical limits: ensuring the formation of a tribofilm that prevents engine wear and lowers high friction. However, it disregards the excessive depletion of the lubricating precursors that make up this protective tribofilm. In this work, the life of oil in lubrication systems for internal combustion engines is analyzed by means of simulations of the mass balances of the protective tribofilm formed inside the engine; results indicate that high lubricant supply rates cause early depletion of lubricant precursors, shortening the life of each batch of oil.

Determination of Takeover Time Budget Based on Analysis of Driver Behavior

An automated driving system notifies a fallback-ready human driver to resume driving when critical operational and functional limits have been or are about to be exceeded. The point between notification and critical limit is the time budget. Previous studies indicate that interdependencies exist between takeover variables and the time budget leading to performance variations and sometimes accidents. It is known that drivers may delay or respond inadequately depending on the time budget. This contribution focuses on utilizing these interdependencies to evaluate the suitability of the time budget for specific scenarios. A 7 s time budget, eight scenarios, and three secondary tasks were studied in a driving simulator with 70 participants aged between 19 Yrs and 41 Yrs. The results indicate that drivers prioritize takeover effort in decreasing order of relative speed, traffic agents, and junctions. Furthermore, 7 s is suitable at a vehicle speed of 80 Km/h to 130 km/h, maximum two traffic agents and three junctions, and handsfree tasks but too high for lower complexities. Generally, the time budget is a sum of the takeover time and maneuver (e.g., lane change) response time. These results are relevant to safety and adaptive variation of the time budget for successful takeover.

MICRONUTRIENT DYNAMICS IN RELATION TO SOIL PROPERTIES IN ARABLE SOILS OF RIGACHIKUN-KADUNA, NORTHERN GUINEA SAVANNAH, NIGERIA

The research was conducted within January 2020 – January 2021 at the arable soils of Rigachikun-Kaduna, Northern Guinea Savanna and intended to study the micronutrient dynamics and relationships with some studied soil properties. Previously harvested maize, cowpea and rice soils (designated as Locations A, B and C respectively) were delineated, and three profile pits dug in each along the line of transect of about 100 m apart. A total of nine profile pits were dug in the three delineations and samples collected from each pit according to their horizonations. The use of Digital Elevation Model (DEM) was employed to study the terrain characteristics of the location. Major micronutrients investigated were Cu, Fe, Zn and Mn. Virtually all micronutrients decreased down the profile in all studied locations with Cu and Zn displaying an irregular trend in all pedons of rice harvested soils in location C. Also Fe rather increased in pedon 1 of location C as well. Cu had positive and non-significant correlation with other micronutrients (Fe and Zn), it however had a significant relationship with Mn. With respect to other soil properties investigated, Cu maintained a negative non-significant correlations. Fe had a positive and highly significant correlation with Mn and Zn. Also, Fe had a significant and negative correlation with organic matter but positive with available phosphorus. Fe was positively but non-significantly correlated with other soil properties such as clay, Ca, Mg, and total exchangeable bases (TEB). There was however, a non-significant and negative correlations of Fe with soil pH, K, Na as well as total exchangeable acidity (TEA). Mn only had significant and positive correlations with all other micronutrients (Cu, Fe and Zn) but non-significantly correlated with other soil properties. Micronutrients were all low to a deficiency level considering their critical limits in the tropical soils. Low organic matter content of soils of Rigachikun may have contributed to low micronutrient reserve of the soils. Activities that will conserve organic matter such as accumulation of litter from harvested crops and alternative means of cattle rearing such ranching rather than freelance grazing should be employed, as efforts to replenish micronutrients through fertilization has not yielded the desired results.

Neotropical stingless bees display a strong response in cold tolerance with changes in elevation.

Tropical pollinators are expected to experience substantial effects due to climate change, but aspects of their thermal biology remain largely unknown. We investigated the thermal tolerance of stingless honey-making bees, the most ecologically, economically and culturally important group of tropical pollinators. We assessed changes in the lower (CTMin) and upper (CTMax) critical thermal limits of 17 species (12 genera) at two elevations (200 and 1500m) in the Colombian Andes. In addition, we examined the influence of body size (intertegular distance, ITD), hairiness (thoracic hair length) and coloration (lightness value) on bees' thermal tolerance. Because stingless beekeepers often relocate their colonies across the altitudinal gradient, as an initial attempt to explore potential social responses to climatic variability, we also tracked for several weeks brood temperature and humidity in nests of three species at both elevations. We found that CTMin decreased with elevation while CTMax was similar between elevations. CTMin and CTMax increased (low cold tolerance and high heat tolerance) with increasing ITD, hair length and lightness value, but these relationships were weak and explained at most 10% of the variance. Neither CTMin nor CTMax displayed significant phylogenetic signal. Brood nest temperature tracked ambient diel variations more closely in the low-elevation site, but it was constant and higher at the high-elevation site. In contrast, brood nest humidity was uniform throughout the day regardless of elevation. The stronger response in CTMin, and a similar CTMax between elevations, follows a pattern of variation documented across a wide range of taxa that is commonly known as the Brett's heat-invariant hypothesis. Our results indicate differential thermal sensitivities and potential thermal adaptations to local climate, which support ongoing conservation policies to restrict the long-distance relocations of colonies. They also shed light on how malleable nest thermoregulation can be across elevations.

Environmental Taxes Impact for the Population Health Protection: Cross-Country Analysis

The current demographic situation in the world encourages the search and implementation of optimal tools for stabilizing the population’s life expectancy and ensuring their health. The study was designed to investigate the impact of environmental taxes, as environmental policy instruments, on the state and the health of the population. The analysis of scientific works, built based on the Publish or Perish software, made it possible to confirm the unfailing relevance of research on the topic of the impact of environmental taxes. Where environmental taxes are considered as a tool for influencing the level of pollution of the surrounding natural Environment and indicators of life and health of the population. The analysis of scientific works published in recent years under the keywords «environmental tax» and «healthy» based on the Scopus scientometric database also confirmed the study’s relevance, considering the level of citations of the presented works. Some authors pay considerable attention to additional taxation of producers of harmful products and subsidizing enterprises that grow or produce eco-products. Other scientists emphasize changing the existing environmental legislation (increasing environmental tax rates, targeted use, introducing additional critical emission limits, etc.). They believe this will have the effect of a hidden intervention in the prevention of disease through reducing climate change. The main part of the study was based on visual confirmation of the relationship between environmental taxes and the population’s level of health using the VOSviewer software product. This bibliometric analysis confirmed that limiting the environmental pollution level due to environmental taxes determines the possibility of improving the population’s health. At the same time, financial instruments for curbing habits harmful to human health also have a positive impact. Clustering made it possible to: confirm the impact of environmental taxes on the actual level of environmental pollution; reflect the dependence of personal habits and tendencies that affect the life and health of the population; to argue the fact that ecological culture and the culture of a healthy lifestyle are formed not only by objective but also by subjective reasons, as well as by the general psychological state of the population; to confirm the existence of the socio-regulatory orientation of the ecological tax, including the environmental exposure and the level of health of the people, etc. The graphical method (built based on Stata software) made it possible to confirm that environmental taxation can improve the state of the natural environment. The transmission nature of environmental taxation’s impact on the population’s life and health is also determined. The research results are a scientific basis for developing the latest environmental policy, which would fully enable the environmental tax to perform its compensatory function, as well as ensure the formation of green production and expand the access of individuals to quality food products.

No consistent effect of daytime versus night-time measurement of thermal tolerance in nocturnal and diurnal lizards.

While essential in understanding impacts of climate change for organisms, diel variation remains an understudied component of temporal variation in thermal tolerance limits [i.e. the critical thermal minimum (CTmin) and maximum (CTmax)]. For example, a higher Ctmax might be expected for an individual if the measurement is taken during the day (when heat stress is most likely to occur) instead of at night. We measured thermal tolerance (Ctmin and Ctmax) during both the daytime and night-time in 101 nocturnal and diurnal geckos and skinks in Hong Kong and in South Africa, representing six species and covering a range of habitats. We found that period of measurement (day vs. night) only affected Ctmin in South Africa (but not in Hong Kong) and that Ctmax was unaffected. Body size and species were important factors for determining Ctmax in Hong Kong and Ctmin in South Africa, respectively. Overall, however, we did not find consistent diel variation of thermal tolerance and suggest that measurements of critical thermal limits may be influenced by timing of measurement-but that such effects, when present, are likely to be context-dependent.

Are Signals of Local Environmental Adaptation Diluted by Laboratory Culture?

Insects have the ability to readily adapt to changes in environmental conditions, however the strength of local environmental adaptation signals under divergent conditions and the occurrence of trait inertia after relaxation of selection, remains poorly understood, especially for traits of climate stress resistance (CSR) and their phenotypic plasticity. The strength of environmental adaptation signals depend on several selection pressures present in the local environment, while trait inertia often occurs when there is a weakening or removal of a source of selection. Here, using Drosophila melanogaster, we asked whether signals of adaptation in CSR traits (critical thermal limits, heat and chill survival and, desiccation and starvation resistance) persist after exposure to laboratory culture for different durations (two vs. ten generations) across four climatically distinct populations. We show that culture duration has large effects on CSR traits and can both amplify or dilute signals of local adaptation. Effects were however dependent upon interactions between the source population, acclimation (adult acclimation at either 18°C, 23°C or 28°C) conditions and the sex of the flies. Trait plasticity is markedly affected by the interaction between the source population, the specific acclimation conditions employed, and the duration in the laboratory. Therefore, a complex matrix of dynamic CSR trait responses is shown in space and time. Given these strong interaction effects, 'snapshot' estimates of environmental adaptation can result in misleading conclusions about the fitness consequences of climate variability.

МОДЕРНІЗАЦІЯ ПІДПРИЄМСТВА ЯК ПЕРЕДУМОВА ЗАБЕЗПЕЧЕННЯ ЙОГО КОНКУРЕНТОСПРОМОЖНОГО РОЗВИТКУ

The article examines the problems of modernization of enterprises as an important prerequisite for ensuring their efficient and competitive development in the long run. The factors that determine the relevance and necessity of modernization of Ukrainian enterprises are systematized. Emphasis is placed on the importance of implementing projects for comprehensive modernization of industrial enterprises of Ukraine, the moral and physical deterioration of production assets, which has crossed critical limits and has become an important reason for reducing the competitiveness of their products. It is proved that modernization is directly related to innovation-oriented solutions in the technological, organizational, managerial, economic and social spheres of the enterprise and is aimed at the development and realization of its economic potential in the long run. The essence of the concept of «modernization of the enterprise» is revealed, its main features are systematized. Emphasis is placed on the fact that the modernization of the enterprise involves its transition to a new quality, not just recovery, development of new competitive advantages that will strengthen the company’s stability in the market in the long run and create conditions for intensifying self-development. The directions, purposes and tools of modernization of the enterprise are defined. The system of competitive advantages of the enterprise which is provided by modernization is characterized. The priority directions and tools of modernization of the Ukrainian enterprises in the conditions of limited resources of their development are substantiated. It is proved that despite the contradictory processes of socio-economic transformations in Ukraine, low rates and quality of economic growth over a long period, the country’s opportunities in the field of innovation development remain high. The fundamental problem of modernization of enterprises is the problem of investment support, which is complex and associated with low efficiency of the institutional environment. It is proposed to consider the processes of modernization of domestic enterprises in the context of reindustrialization of the country’s industrial complex. The implementation of such a task requires not only indirect state participation, but also direct, which involves the development of specific mechanisms to stimulate modernization processes.

CHARACTERIZATION AND CLASSIFICATION OF SOILS ALONG RIVER DONGA, DONGA, TARABA STATE, NIGERIA

This study was carried out to ascertain the characterization and classification of soils along river Donga in Donga local government area of Taraba State. Three profile pits were dug on the flat terrain for the physio-chemical properties of the soils. The pits were described and samples were collected for routine laboratory analysis for the selected physio-chemicals properties. Data collected were analyzed statistically using analysis of variance (ANOVA) The result of the laboratory analysis of the physical and chemical properties indicated that particle size distribution of sand particle dominated other fraction of fine earth materials. This can be attributed to the parent materials that gave rise to the soils.The pH (H2O) was slightly acidic in reaction in all the pedons studied (6.44, 5.82 and 5.67). The organic carbon content ranges from very low to low compared to the maximum level (5%) for tropical soils. Available phosphorus obtained exceeded the critical limits of 8.0 to &gt;18mg/kg, which indicates that the available phosphorus were high. The exchangeable bases (Ca, Mg, K &amp; Na) as indicated in the table 3 that Ca, Mg, K &amp; Na were low in all the pedons studied. The results obtained from analyzed profile samples showed that percentage (%) base saturation values for all the pedons were high. The Correlation was done to determine non-significant and significant values among soil physio-chemical properties studied at 5% and 1% probability level. In addition, after the profile description and examination of the soil properties of the study area, the soils were classified using USDA soil taxonomy (2014). Pedons 1 and 2 are classified into the order of Alfisols and sub-group of Typical Haplustalf while pedon 3 is also classified into Alfisols but sub-group of Arenickandiustals (Hypereuticlixisels).