Ecotoxicokinetics as a section of ecotoxicology (review)

This paper discusses differences in chemical elements concentration by the components of an ecosystem exposed to the refinery, relative to the territory taken as the background. The study was conducted in the Antipinsky Oil Refinery location area, the territory of the Tyumen Federal Reserve was considered as the background. The change in the elemental composition of the soil, bedding, grass stand, and birch leaves has been studied. The study was carried out by instrumental neutron activation and atomic absorption analysis methods. For all considered components of ecosystems, the patterns of the spatial distribution of elements with respect to refinery were analyzed (both to remote and to cardinal directions). The change in the associations of chemical elements in technogenic conditions was studied. The obtained results were compared with the clarke and literature data, on the basis of which the background status of the natural territory was confirmed, and low pollution of the technogenic region was revealed. According to the results, an elevated content of many of the studied chemical elements in the upper soil horizon was found. For most of them, a change in the distribution over the profile was recorded. The greatest pollution among the studied objects is characteristic of birch leaves. The spatial distribution of pollution is different for the components considered, but is consistent with the predominant wind direction. In the studied components of the technogenic ecosystem, an accumulation of elements specific to the oil refining industry was found: Br, Sb, La, Tb, Yb, Ce, As, Hg, Zn, Co. In all considered components of the technogenic ecosystem a violation of correlations and the presence of specific associations were recorded.

In order to solve the problems of single monitoring factor, weak comprehensive analysis ability, and poor real time performance in traditional environmental monitoring systems, a research method of residential environment pollution monitoring system based on cloud computing and Internet of Things is proposed. The method mainly includes two parts: an environmental monitoring terminal and an environmental pollution monitoring and management platform. Through the Wi-Fi module, the data is sent to the environmental pollution monitoring and management platform in real time. The environmental monitoring management platform is mainly composed of environmental pollution monitoring server, web server, and mobile terminal. The results are as follows. The data measured by the system is close to the data measured by the instrument, and the overall error is small. The measurement error of harmful gases is about 6%. PM 2.5 is about 6.5%. Noise is about 1%. The average time for sensor data update is 0.762 s. The average alarm response time is 2 s. The average data transfer time is 2 s. Practice has proved that the environmental pollution monitoring and alarm system operates stably and can realize real-time collection and transmission of data such as noise, PM 2.5, harmful gas concentration, illumination, GPS, and video images, providing a reliable guarantee for timely environmental pollution control.

There is increasing evidence that closely related species have contrasting ecosystem effects, but very little is known about the temporal scale of these effects. When organisms' ecosystem-effects persist beyond or emerge after their presence in the ecosystem, this might increase the potential for eco-evolutionary feedbacks to accompany evolutionary diversification. Here we studied lab-raised whitefish of a benthic-limnetic species pair from a postglacial adaptive radiation to test whether closely related species have contrasting effects on mesocosm ecosystems (hereafter ecosystem effects). We found that the presence of whitefish (ecological effect) had strong effects on some ecosystem components, for example by reducing snail and mussel abundance and increasing phytoplankton abundance. Whitefish species had contrasting effects (evolutionary effect) on benthic algal cover, dissolved organic carbon, and zooplankton community composition, but these effects only emerged several months after whitefish were rem...

The entrepreneurial ecosystem is a relatively new perspective within the field of entrepreneurship but is now one of the most discussed topics in that field. It emphasizes the role of broader framework conditions that promote or constrain entrepreneurial activity in any region. The supportive institutional framework (reduced number of government regulations, ease in compliance of taxation system and control over corruption) and physical conditions (ease in access to finance, developed infrastructure, stability in political environment, the availability of an educated workforce and reduced competition with informal sector) create an entrepreneurial ecosystem where entry, survival and growth of firms will be at the highest rate. These elements of the institutional framework and physical conditions are interactive in nature, therefore, policymakers around the world are trying to achieve a balance between these components of the entrepreneurial ecosystem. There is a paucity of research on the entrepreneurial ecosystems of developing countries, therefore, the findings of this thesis will not only be an addition to the literature but will also be useful for policymakers in these countries. In this study, pooled cross-sectional data for Pakistan and 41 low-middle income countries (LMICs) covering the period 2006-13 have been used to identify different entrepreneurial ecosystems and explain their impact on the performance of small and medium enterprises (SMEs). The performance of SMEs has been measured through the annual change in sales growth, employment growth and labour productivity growth. The findings based on the analysis of the entrepreneurial ecosystems for the group of LMICs show that all of the identified components can have a negative effect on the performance of the SMEs. However, ranking of components on the basis of magnitude and statistical significance of effect shows that corruption has the most negative effect on firm performance, which warranted further examination. Therefore, we compare the firm performance of the most corrupt and least corrupt LMICs through the use of propensity score matching (PSM) methods. The results of matching methods show that firm performance in the most corrupt countries is at least 10% lower than firms in the least corrupt countries. Thus, LMICs need to take steps to improve their control over corruption in order to achieve better performance of their SMEs. However, only the individual components of the entrepreneurial ecosystems could be assessed for LMICs because of the heterogeneity of the institutional frameworks and physical conditions of these countries. Therefore, the entrepreneurial ecosystem of Pakistan has also been analysed to determine its existence and composition, and its effects on the performance of SMEs. The entrepreneurial ecosystem of Pakistan is examined using firm level survey data provided by the World Bank Enterprise Survey (WBES) for the years 2007 and 2013. A cluster analysis and canonical discriminant analysis (CDA) is undertaken to identify the composition of the entrepreneurial ecosystem existing in Pakistan. This bottom-up approach, recommended in the literature, has been used to measure the interactive effects of components of the entrepreneurial ecosystem of Pakistan. None of the studies in the literature has measured and empirically tested the entrepreneurial ecosystem of Pakistan using this approach. The findings indicate that the entrepreneurial ecosystem of Pakistan is a combination of elements of the institutional framework and physical conditions. Except for government regulations and political stability, all other components contribute negatively to the entrepreneurial ecosystem of Pakistan. Thus, the aggregate effect of the entrepreneurial ecosystem is negative on the performance of SMEs. Moreover, an index was calculated using the interactive weighted effect of the components of the entrepreneurial ecosystem of Pakistan. The regression estimates based on the index values affirmed the negative effect of the entrepreneurial ecosystem of Pakistan as a system. Our findings for Pakistan can be used as a guideline for policymakers in other developing countries with similar institutional frameworks and physical conditions. However, it can be inferred that there is no shortcut to create a supportive entrepreneurial ecosystem. The gradual improvements, with government acting as facilitator, are required to make the entrepreneurial ecosystems in LMICs conducive for entry, survival and growth of businesses. The specific recommendations for both policymakers and entrepreneurs are given at the end of the thesis.

Genetically modified strains usually are generated within defined genetic backgrounds to minimize variation for the engineered characteristic in order to facilitate basic research investigations or for commercial application. However, interactions between transgenes and genetic background have been documented in both model and commercial agricultural species, indicating that allelic variation at transgene-modifying loci are not uncommon in genomes. Engineered organisms that have the potential to allow entry of transgenes into natural populations may cause changes to ecosystems via the interaction of their specific phenotypes with ecosystem components and services. A transgene introgressing through natural populations is likely to encounter a range of natural genetic variation (among individuals or sub-populations) that could result in changes in phenotype, concomitant with effects on fitness and ecosystem consequences that differ from that seen in the progenitor transgenic strain. In the present study, using a growth hormone transgenic salmon example, we have modeled selection of modifier loci (single and multiple) in the presence of a transgene and have found that accounting for genetic background can significantly affect the persistence of transgenes in populations, potentially reducing or reversing a “Trojan gene” effect. Influences from altered life history characteristics (e.g., developmental timing, age of maturation) and compensatory demographic/ecosystem controls (e.g., density dependence) also were found to have a strong influence on transgene effects. Further, with the presence of a transgene in a population, genetic backgrounds were found to shift in non-transgenic individuals as well, an effect expected to direct phenotypes away from naturally selected optima. The present model has revealed the importance of understanding effects of selection for background genetics on the evolution of phenotypes in populations harbouring transgenes.

Stram, D. L., and Evans, D. C. K. 2009. Fishery management responses to climate change in the North Pacific. – ICES Journal of Marine Science, 66: 1633–1639. In the North Pacific, warming trends, coupled with declining sea ice, raise concerns about the effects of climate change on fish populations and ecosystem dynamics. Scientists are only beginning to understand the potential feedback mechanisms that will affect everything from plankton populations to major commercial fish species distributions, yet fishery managers have a responsibility to prepare for and respond to changing fishing patterns and potential ecosystem effects. There are ways for fishery managers to be proactive, while waiting for better information to unfold. The North Pacific Fishery Management Council (Council) and the National Marine Fisheries Service have jurisdiction over offshore fisheries in Alaska, USA. Recently, the Council has undertaken risk-averse management actions, in light of uncertainty about the effects of warming trends (and loss of sea ice) and resulting changes to fishing activities in the North Pacific. The Council has assessed whether opportunities for unregulated fishing could result from changes in fish distribution, has closed the Arctic Ocean to all commercial fishing pending further research, and has established extensive area closures where fishing with bottom-trawl gear is prohibited to protect vulnerable crab habitat and to control the northern expansion of the trawl fleet into newly ice-free waters. In cases where linkages between climate variables and fish distributions can be identified, the Council is developing adaptive management measures to respond to varying distributions of fish and shellfish. Finally, the Council has also tried to re-examine existing information to gain a better understanding of climate and ecosystem effects on fishery management. The pilot Fishery Ecosystem Plan for the Aleutian Islands maps interactions among climate factors and ecosystem components and suggests indicators for the Council to monitor.

A growing body of literature documents that spawning Pacific salmon have profound effects on terrestrial and aquatic ecosytems. This has led to calls for considering ecosystem effects in setting salmon escapement goals; most stocks, however, are still managed using single-species stock-recruit models. Our objective is to ascertain whether current knowledge is adequate for setting ecosystem-based escapement goals, with particular reference to Alaskan fisheries. We review the literature to determine how well the quantitative relationships between salmon and a given ecosystem component (e.g., the growth rate of a given species) have been identified. In most cases, quantitative relationships are not available for a wide enough range of physical and biological conditions to make accurate predictions of the response to a given level of salmon escapement. Thus, fisheries managers might curretly have difficulty in justifying ecosystem-based escapement goals. We discuss the potential costs and benefits of increasing escapement goals as a precautionary approach, and the possibility of managing for key species for which quantitative data do exist. We conclude that developing ecosystem-based escapement goals will require better collaboration between researchers and managers. Even under the best of circumstances, however, it will be a long-term process, and the results are likely to be site-specific.

Environmental monitoring of national highway is an important content of China’s environmental monitoring network in the transport field, a part of national environmental monitoring system, and also a significant basis for environmental protection supervision and management of the transport industry. Using the methods of spatial analysis, grid analysis, and optimization through ArcGIS, monitoring objects of Chinese national highway environmental monitoring network had been screened out. Among which, the environmental quality monitoring objects are composed of the national highway sensitive sections nearby or passing through 277 natural reserves, 32 national scenic areas, 7 of the world’s natural and cultural heritage sites, 8 important wetlands, 398 important reservoirs, and 193 state-level sensitive aquatic germ plasm resources conservation areas; and the pollutant emission monitoring objects include 316 long and extra-long tunnels, 539 service areas and 601 toll stations with large traffic volume. Environmental quality monitoring objects and pollutant emission monitoring objects form China’s National Highway Environmental Monitoring Network, which has filled the blank of highway environmental monitoring in the national environmental monitoring network. It will play a positive role in promoting the green development of China's transport industry.

Global patterns for the spatial distribution of floating microfibers: Arctic Ocean as a potential accumulation zone

A decision framework for hemlock woolly adelgid management: Review of the most suitable strategies and tactics for eastern Canada

Fire has always been an important component of many ecosystems, but anthropogenic global climate change is now altering fire regimes over much of Earth's land surface, spurring a more urgent need to understand the physical, biological, and chemical processes associated with fire as well as its effects on human societies. In 2020, AGU launched a Special Collection that spanned 10 journals, soliciting papers under the theme “Fire in the Earth System” to encourage state‐of‐the‐art publications in fire‐related science. The completed Special Collection comprises more than 100 papers. Here, we summarize the articles published in this collection, considering them to be grouped into seven themes: paleofire and its ties to climate; evolution of fire patterns in the recent past and the future, including the effects of ongoing climate change; physical (atmospheric) and chemical processes associated with fire; ecosystem effects, including on biogeochemical cycles; physical landscape change after fire and its associated hazards; fire effects on water quality, air quality, and human health; and new methods and technologies applied to fire research.

Biological invasions are a principal threat to global biodiversity. Omnivores, such as crayfish, are among the most important groups of invaders. Their introduction often results in biodiversity loss, particularly of their native counterparts. Managed relocations of native crayfish from areas under threat from invasive crayfish into isolated 'ark sites' are sometimes suggested as a conservation strategy for native crayfish; however, such relocations may have unintended detrimental consequences for the recipient ecosystem. Despite this, there have been few attempts to quantify the relative impacts of native and invasive crayfish on aquatic ecosystems. To address this deficiency we conducted a meta-analysis on the effects of native and invasive crayfish on nine ecosystem components: decomposition rate, primary productivity, plant biomass, invertebrate density, biomass and diversity, fish biomass and refuge use, and amphibian larval survival. Native and invasive crayfish significantly reduced invertebrate density and biomass, fish biomass and amphibian survival rate and significantly increased decomposition rates. Invasive crayfish also significantly reduced plant biomass and invertebrate diversity and increased primary productivity. These results show that native and invasive crayfish have wide-ranging impacts on aquatic ecosystems that may be exacerbated for invasive species. Subsequent analysis showed that the impacts of invasive crayfish were significantly greater, in comparison to native crayfish, for decomposition and primary productivity but not invertebrate density, biomass and diversity. Overall, our findings reconfirm the ecosystem altering abilities of both native and invasive crayfish, enforcing the need to carefully regulate managed relocations of native species as well as to develop control programs for invasives.

<p>Chemical pollution of the environment is one of the most serious problems for mankind in the modern time. The main sources of pollutants entering the environment are atmospheric emissions of industrial enterprises, ore dumps and wastes released by the chemical industry. However, regardless of the source of the pollutants, the main function in reducing environmental risk is performed by the soil. With the increasing anthropogenic load on natural landscapes and agricultural lands, reliable data on the toxicity of heavy metals (HM) as well as the mechanisms of their entry into the plants are needed to carry out environmental monitoring and quality control of grown products.</p><p>The accumulation and transformation of Ni, Mn, Zn, Cu, Cr, Cd, and Pb in soils of steppe zone of southern Russia were studied under different sources of pollution: aerotechnogenic emissions by Novocherkassk power station and industrial effluents of the chemical plant near Kamensk-Shakhtinskii city. The author’s method for determining the HM compounds composition in the soil (Minkina et al., 2008) was used to assess the ecological situation of the impacted territory. It was found that the total content of HM in the soils of the impacted territories exceeded Clarke value, especially for Zn (up to 796 times).</p><p>The patterns of accumulation and distribution of Ni, Mn, Zn, Cu, Cr, Cd, and Pb were determined for the most common species of wild-growing and agricultural herbaceous plants of the Poaceae (Triticum aestivum, Hordeum sativum, Poa pratensis L.), and Asteraceae (Ambrosia artemisiifolia, Achillea nobilis, Tanacetum vulgare) that grew in the impacted territory. Agricultural and wild herbaceous plants growing 1.5–2.2 km from the power station are polluted with Pb, Zn, Ni and Cd.</p><p>It was shown that even in conditions of extreme soil pollution by industrial effluents, the root system of the plants successfully performed its protective function: the HM content in roots significantly exceeded it in above-ground part. At the same time, the pollutants concentration ratio in the above-ground part and in the roots was higher under aerotechnogenic pollution due to the additional receipt of the HM through the surface of the leaves. The dependence between HM accumulation and distribution in plants and the content of mobile metal compounds in the soil was established (correlation coefficient=0.79).</p><p>The extreme HM contamination effect on the anatomical and morphological characteristics and ultrastructure of the cultivated and wild plants was studied by transmission electron microscopy. The differences in adaptation of the plants to the effects of a stressful environmental factor were manifested not only in the external structure but also at the anatomical and intracellular levels of organization. In the samples contaminated with HM, parenchyma cell vacuoles contained electron-dense inclusions grouped in the center of the vacuole which were probably the deposits of metal compounds. Cultivated herbaceous plants of Poaceae family were found to be more susceptible to anthropogenic pollution with HMs compared to the wild plants of the same family.</p><p>Research was supported by the Grant of the President of the Russian Federation, project no. MK-2818.2019.5, RFBR, project no. 19-29-05265.</p>

The regional-scale importance of an aquatic stressor depends both on its regional extent (i.e., how widespread it is) and on the severity of its effects in ecosystems where it is found. Sample surveys, such as those developed by the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP), are designed to estimate and compare the extents, throughout a large region, of elevated conditions for various aquatic stressors. In this article, we propose relative risk as a complementary measure of the severity of each stressor's effect on a response variable that characterizes aquatic ecological condition. Specifically, relative risk measures the strength of association between stressor and response variables that can be classified as either "good" (i.e., reference) or "poor" (i.e., different from reference). We present formulae for estimating relative risk and its confidence interval, adapted for the unequal sample inclusion probabilities employed in EMAP surveys. For a recent EMAP survey of streams in five Mid-Atlantic states, we estimated the relative extents of eight stressors as well as their relative risks to aquatic macroinvertebrate assemblages, with assemblage condition measured by an index of biotic integrity (IBI). For example, a measure of excess sedimentation had a relative risk of 1.60 for macroinvertebrate IBI, with the meaning that poor IBI conditions were 1.6 times more likely to be found in streams having poor conditions of sedimentation than in streams having good sedimentation conditions. We show how stressor extent and relative risk estimates, viewed together, offer a compact and comprehensive assessment of the relative importances of multiple stressors.

BackgroundArbuscular mycorrhizal fungi (AMF) can form obligate symbioses with the vast majority of land plants, and AMF distribution patterns have received increasing attention from researchers. At the local scale, the distribution of AMF is well documented. Studies at large scales, however, are limited because intensive sampling is difficult. Here, we used ITS rDNA sequence metadata obtained from public databases to study the distribution of AMF at continental and global scales. We also used these sequence metadata to investigate whether host plant is the main factor that affects the distribution of AMF at large scales.ResultsWe defined 305 ITS virtual taxa (ITS-VTs) among all sequences of the Glomeromycota by using a comprehensive maximum likelihood phylogenetic analysis. Each host taxonomic order averaged about 53% specific ITS-VTs, and approximately 60% of the ITS-VTs were host specific. Those ITS-VTs with wide host range showed wide geographic distribution. Most ITS-VTs occurred in only one type of host functional group. The distributions of most ITS-VTs were limited across ecosystem, across continent, across biogeographical realm, and across climatic zone. Non-metric multidimensional scaling analysis (NMDS) showed that AMF community composition differed among functional groups of hosts, and among ecosystem, continent, biogeographical realm, and climatic zone. The Mantel test showed that AMF community composition was significantly correlated with plant community composition among ecosystem, among continent, among biogeographical realm, and among climatic zone. The structural equation modeling (SEM) showed that the effects of ecosystem, continent, biogeographical realm, and climatic zone were mainly indirect on AMF distribution, but plant had strongly direct effects on AMF.ConclusionThe distribution of AMF as indicated by ITS rDNA sequences showed a pattern of high endemism at large scales. This pattern indicates high specificity of AMF for host at different scales (plant taxonomic order and functional group) and high selectivity from host plants for AMF. The effects of ecosystemic, biogeographical, continental and climatic factors on AMF distribution might be mediated by host plants.