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A field study was carried out to estimate the variations in the concentrations of macro- and trace elements in the rhizosphere soil and in roots and leaves of three widely distributed plant species-couch grass, plantain, and yarrow collected simultaneously from two sites characterized by different soil parameters. Main attention was paid to environmental (soil characteristics) and phylogenetic (plant species) factors that can influence on the concentrations of different elements in the plants and in soils. Both the factors cannot be considered as independent, although their contribution to the plant elemental composition may be different. There were statistically significant differences between concentrations of C, N, and H and 13 macro- and trace elements in the soils collected from the two sites. The concentrations of many chemical elements in the rhizosphere soil of the three plant species collected from the same site were often different. The differences in the characteristics of the soils at the sites resulted in differences between the concentrations of several elements in the plants growing at the sites. However, this was only one of the reasons of significant difference between the concentrations of macro- and trace elements in the same plant species collected from the sites. Couch grass, plantain, and yarrow had different reactions on the soil characteristics. The elemental composition of each plant species was unique although they grew at the same place and were collected simultaneously. Among the plants, yarrow was more tolerant to varying environmental conditions than plantain and couch grass.

Ammonia (NH 3 ) emissions from traffic have received particular attention in recent years because of their important contributions to the growth of secondary aerosols and the negative effects on urban air quality. However, few studies have been performed on the impacts of traffic NH 3 emissions on adjacent soil and plants. Moreover, doubt remains over whether dry nitrogen (N) deposition still contributes a minor proportion of plant N nutrition compared with wet N deposition in urban road environments. This study investigated the δ 15 N values of road dustfall, soil, moss, camphor leaf and camphor bark samples collected along a distance gradient from the road, suggesting that samples collected near the road have significantly more positive δ 15 N values than those of remote sites. According to the SIAR model (Stable Isotope Analysis in R) applied to dustfall and moss samples from the roadside, it was found that NH 3 from traffic exhaust (8.8 ± 7.1%) contributed much less than traffic-derived NO 2 (52.2 ± 10.0%) and soil N (39.0 ± 13.8%) to dustfall bulk N; additionally, 68.6% and 31.4% of N in mosses near the roadside could be explained by dry N deposition (only 20.4 ± 12.5% for traffic-derived NH 3 ) and wet N deposition, respectively. A two-member mixing model was used to analyse the δ 15 N in continuously collected mature camphor leaf and camphor bark samples, which revealed a similarity of the δ 15 N values of plant-available deposited N to 15 N-enriched traffic-derived NO x -N. We concluded that a relatively high proportion of N inputs in urban road environments was contributed by traffic-related dustfall and NO x rather than NH 3 . These information provide useful insights into reducing the impacts of traffic exhaust on adjacent ecosystems and can assist policy makers in determining the reconstruction of a monitoring network for N deposition that reaches the road level., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Soils can be contaminated by pharmaceuticals. The aim of this study was to evaluate the impact of soil conditions (influencing sorption and persistence of pharmaceuticals in soils) and plant type on the root uptake of selected pharmaceuticals and their transformation in plant-soil systems. Four plants (lamb's lettuce, spinach, arugula, radish) planted in 3 soils were irrigated for 20 days (26) with water contaminated by one of 3 pharmaceuticals (carbamazepine, atenolol, sulfamethoxazole) or their mixture. The concentrations of pharmaceuticals and their metabolites in soils and plant tissues were evaluated after the harvest. Sulfamethoxazole and atenolol dissipated rapidly from soils. The larger concentrations of both compounds and an atenolol metabolite were found in roots than in leaves. Sulfamethoxazole metabolites were below the limits of quantifications. Carbamazepine was stable in soils, easily uptaken, accumulated, and metabolized in plant leaves. The efficiency of radish and arugula (both family Brassicaceae) in metabolizing was very low contrary to the high and moderate efficiencies of lamb's lettuce and spinach, respectively. Compounds' transformations mostly masked the soil impact on their accumulation in plant tissues. The negative relationships were found between the carbamazepine sorption coefficients and its concentrations in roots of radish, lamb's lettuce, and spinach.

The nitrogen (N) utilization strategy of plants has become a topic of interest within the field of phytoecology. However, few studies have considered N cycling on coral island ecosystems from the perspective of their evolution. The aim of this study was to test the impacts of biological transport by seabirds, on the sources and uses of N by plants, and pathways of N cycling in soil-plant ecosystems on coral islands. A series of eight coral islands were investigated, five of which were affected to a varying extent by seabirds. The total phosphorus (TP) concentration from avian sources and the δ 15 N values of total nitrogen (TN) and inorganic nitrogen (IN: NH 4 + -N, and NO 3 - -O, in soils were determined, as well as proxies in plant leaves of two dominant plant species, including TN, the carbon/nitrogen ratio (C/N), and δ 18 O of NO 3 - N values in soils all increased. Plant C/N and δ 13 C and δ 15 N values. The results show that, with an increase of TP, the TN and IN content, and δ 15 N values in soils all increased. Plant C/N and δ 15 N values decreased and increased, respectively, as the soil N content increased. When the TN content of the soil was low, the δ 15 N values were similar. Both plants and soil were probably N-limited prior to seabird colonization, with the N source on the barren coral islands originating primarily from atmospheric deposition. With seabird guano input and subsequent pedogenesis, the source of N switched to guano. Under these conditions, most of the N utilized by plants originated from NH 3 - , but was much lower than that in soil NH 4 + . When the soil TN content was high, the δ 15 N values were similar. Both plants and soil were probably N-limited prior to seabird colonization, with the N source on the barren coral islands originating primarily from atmospheric deposition. With seabird guano input and subsequent pedogenesis, the source of N switched to guano. Under these conditions, most of the N utilized by plants originated from NH 4 + , while nitrate is dominant for non-seabirds islands. Seabird activities have played a key role in the N dynamics of soil-plant ecosystems at coral islands., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Fifty years ago, Ehrlich and Raven proposed that insect herbivores have driven much of plant speciation, particularly at tropical latitudes. There have been no explicit tests of their hypotheses. Indeed there were no proposed mechanisms either at the time or since by which herbivores might generate new plant species. Here we outline two main classes of mechanisms, prezygotic and postzygotic, with a number of scenarios in each by which herbivore-driven changes in host plant secondary chemistry might lead to new plant lineage production. The former apply mainly to a sympatric model of speciation while the latter apply to a parapatric or allopatric model. Our review suggests that the steps of each mechanism are known to occur individually in many different systems, but no scenario has been thoroughly investigated in any one system. Nevertheless, studies of Dalechampia and its herbivores and pollinators, and patterns of defense tradeoffs in trees on different soil types in the Peruvian Amazon provide evidence consistent with the original hypotheses of Ehrlich and Raven. For herbivores to drive sympatric speciation, our findings suggest that interactions with both their herbivores and their pollinators should be considered. In contrast, herbivores may drive speciation allopatrically without any influence by pollinators. Finally, there is evidence that these mechanisms are more likely to occur at low latitudes and thus more likely to produce new species in the tropics. The mechanisms we outline provide a predictive framework for further study of the general role that herbivores play in diversification of their host plants., (© 2016 by the Ecological Society of America.)

Exurban residential land (one housing unit per 0.2-16.2 ha) is growing in importance as a human-dominated land use. Carbon storage in the soils and vegetation of exurban land is poorly known, as are the effects on C storage of choices made by developers and residents. We studied C storage in exurban yards in southeastern Michigan, USA, across a range of parcel sizes and different types of neighborhoods. We divided each residential parcel into ecological zones (EZ) characterized by vegetation, soil, and human behavior such as mowing, irrigation, and raking. We found a heterogeneous mixture of trees and shrubs, turfgrasses, mulched gardens, old-field vegetation, and impervious surfaces. The most extensive zone type was turfgrass with sparse woody vegetation (mean 26% of parcel area), followed by dense woody vegetation (mean 21% of parcel area). Areas of turfgrass with sparse woody vegetation had trees in larger size classes (> 50 cm dbh) than did areas of dense woody vegetation. Using aerial photointerpretation, we scaled up C storage to neighborhoods. Varying C storage by neighborhood type resulted from differences in impervious area (8-26% of parcel area) and area of dense woody vegetation (11-28%). Averaged and multiplied across areas in differing neighborhood types, exurban residential land contained 5240 ± 865 g C/m 2 in vegetation, highly sensitive to large trees, and 13 800 ± 1290 g C/m 2 in soils (based on a combined sampling and modeling approach). These contents are greater than for agricultural land in the region, but lower than for mature forest stands. Compared with mature forests, exurban land contained more shrubs and less downed woody debris and it had similar tree size-class distributions up to 40 cm dbh but far fewer trees in larger size classes. If the trees continue to grow, exurban residential land could sequester additional C for decades. Patterns and processes of C storage in exurban residential land were driven by land management practices that affect soil and vegetation, reflecting the choices of designers, developers, and residents. This study provides an example of human-mediated C storage in a coupled human-natural system., (© 2016 by the Ecological Society of America.)

Background: Plants can utilize two major forms of inorganic N: NO3(-) (nitrate) and NH4(+) (ammonium). In some cases, the preference of one form over another (denoted as β) can appear to be quite pronounced for a plant species, and can be an important determinant and predictor of its distribution and interactions with other species. In many other cases, however, assignment of preference is not so straightforward and must take into account a wide array of complex physiological and environmental features, which interact in ways that are still not well understood., Scope: This Viewpoint presents a discussion of the key, and often co-occurring, factors that join to produce the complex phenotypic composite referred to by the deceptively simple term 'N-source preference'., Conclusions: N-source preference is much more complex a biological phenomenon than is often assumed, and general models predicting how it will influence ecological processes will need to be much more sophisticated than those that have been so far developed.

In order to deepen our understanding of the ecosystems around thermal springs and contribute to their preservation and enhancement, our study focused on the physico-chemical analysis of soils located in the immediate vicinity of two thermal springs Ain El Haouamed (S1) and Ain Hamra (S2) in the eastern region of Morocco. At the same time, we identified the plants that thrive in these areas and have developed specific adaptations to particular environmental conditions. The results of physico-chemical soil analyses revealed distinct characteristics. Around the first thermal spring (S1), the soil has a sandy loam texture, while around the second spring (S2), a clayey loam texture. The pH of both soils is slightly basic. In terms of organic matter, significant variations were observed between soil samples taken in these areas. Electrical conductivity and other physico-chemical parameters showed variable values. A study of the vegetation near the thermal springs shows the presence of (Matricaria chamomilla, Juncus acutus, Carex sylvatica) at site 1 and (Tamarix gallica, Inula viscosa, Phragmites australis, Typha angustifolia) at site 2. This information will certainly contribute to a better understanding of these specific thermal ecosystems. The present study has led to the identification of several plant species of great interest, representing an important advance in our knowledge of the biodiversity of these areas. These results can also be used to develop strategies for the preservation and sustainable management of these particular ecosystems. [ABSTRACT FROM AUTHOR]

The results of research on the content of water-soluble fluorine in the soils and vegetation of the Carpathian Biosphere Reserve (KBR) are presented. Analyzes were performed using a spectrometric spectrometer with aliza­rin-complexone on a Specol 11 spectrophotometer. Based on the results of statistical processing of the analysis, the limits and background content of water-soluble fluorine were established in soils on the plots: Yasynska — 0.1— 1.34 mg/kg (background — 1.1 mg/kg); Rakhivska — 0.1—2.86 mg/kg (background — 1.4 mg/kg); Bohdanska — 1.34—1.9 mg/kg, (background — 1.6 mg/kg) (total background content — 1.34 mg/kg). It was determined that in the soils of the areas located in the zone of tectonic disturbance (v. Kvasy) the content of fluorine is greater than the background (1.35—1.4 mg/kg), its intake occurs together with mineral waters and gases. It was found that the maximum content of water-soluble fluorine (1.6—2.6 mg/kg) in in sod-podzolic soils (light and medium loamy) of the Marmaros massif, which is associated with increased humidity and the presence of kaolinite component of clay minerals, which does not bind fluorine into hard-to-reach compounds, subalpine) and the content of water-soluble fluorine in soils, at the same time, a weak negative relationship between the steepness of slopes (gentle, steep, precipitous) and the content of water-soluble fluorine in soils (the lower the steepness of the slope, the higher the content of water-soluble fluorine) was found. Biogeochemical properties for water-soluble fluorine (according to the biological absorption coefficient, Ax) of nine types of plants were established: evergreen conifers (pins and branches) — Táxus baccátaL. — 15.5; Thuja — 5, Abies alba — 5; birch family (branches and leaves) — Corylus avellana L. — 6.1, Alnus glutinosa (L.) P. Gaertn — 2.8; grasses (leaves and flowers) — Betonica officinalis L. — 4.6, Centauréa jacea — 6, Senecio vulgaris L. — 4.3, Filipendula ulmaria — 3.9. The concentrator of water-soluble fluorine is the pins and branches of the Taxus baccata L. [ABSTRACT FROM AUTHOR]

This study aims to compare the impact mechanisms of soil reinforcement by plants in the Jinyun Mountain area of Chongqing and the loess hilly area of Yan'an City, Shanxi Province, China. A systematic analysis was performed on the root morphological and soil mechanical parameters of trees (Rhus typhina and Ulmus pumila) and shrubs (Vitex negundo and Ziziphus jujuba). Four species were then selected to determine the soil shear strength. The RBMw model was employed to calculate the soil reinforcement benefits provided by these plants. The soil reinforcement of different plant species was evaluated to explore the components and contributions of soil reinforcement benefits. The results showed that: 1) The V. negundo shared the largest values for the root length per unit root volume, total root surface area, number of root forks, and root tips, while the R. typhina was the smallest values among the four species. There were no significant differences in the average root diameter of the four species. Moreover, the root length, number of root forks, and number of root tips of the R. typhina and U. pumila planted in Chongqing were significantly higher than those in Yan'an. While the V. negundo and R. typhina showed no significant differences. 2) The root tensile strength was inversely related to the root diameter in a power-law function. The V. negundo shared the highest average tensile strength. There was no significant difference of tensile strength of roots from the same plant species between different regions. By contrast, the V. negundo roots exhibited the higher tensile strength in Chongqing, compared with Yan'an. 3) The root systems of the four plant species were provided soil reinforcement efficiencies ranging from 0.65 to 4.12 kPa, with the significant differences among species. Among individual plants, V. negundo in Chongqing exhibited the highest soil reinforcement effects, while Z. jujuba was the lowest in Yan'an. The highest soil reinforcement efficiency was observed in the R. typhina in Chongqing, whereas, the lowest was found in the U. pumila in Yan'an. The root-soil composite effective cohesion of the two tree species planted in Chongqing was higher than that of bare soil (by 10%), while the shrubs was generally slightly lower. The root-soil composite shear strength in the V. negundo planting area was approximately 50% lower than that of the bare soil. The soil effective cohesion significantly decreased in the first year of V. negundo planting in Chongqing. The root system of V. negundo in Chongqing was contributed 30% to the root-soil composite effective cohesion, followed by the R. typhina in Chongqing (21.30%), and the U. pumila in Yan'an was the lowest (3.63%). The soil reinforcement effects and efficiencies of the four tree species planted in Chongqing were significantly higher than those in Yan'an. There was no variation in the exception of the individual soil reinforcement efficiency of Z. jujuba. The soil under R. typhina exhibited the highest comprehensive soil cohesion, while the high number of roots of V. negundo was resulted in the extremely low soil shear strength, leading to the soil cohesion lowest in the V. negundo planting area. As such, plants can be expected to reinforce the soil via their root systems. The finding can provide the theoretical basis to select the tree species for soil reinforcement and slope protection in different regions. [ABSTRACT FROM AUTHOR]

Summary: Many plant species are predicted to migrate poleward in response to climate change. Species distribution models (SDMs) have been widely used to quantify future suitable habitats, but they often neglect soil properties, despite the importance of soil for plant fitness. As soil properties often change along latitudinal gradients, higher‐latitude soils might be more or less suitable than average conditions within the current ranges of species, thereby accelerating or slowing potential poleward migration.In this study, we built three SDMs – one with only climate predictors, one with only soil predictors, and one with both – for each of 1870 plant species in Eastern North America, in order to investigate the relative importance of soil properties in determining plant distributions and poleward shifts under climate change.While climate variables were the most important predictors, soil properties also had a substantial influence on continental‐scale plant distributions. Under future climate scenarios, models including soil predicted much smaller northward shifts in distributions than climate‐only models (c. 40% reduction).Our findings strongly suggest that high‐latitude soils are likely to impede ongoing plant migration, and they highlight the necessity of incorporating soil properties into models and predictions for plant distributions and migration under environmental change. See also the Commentary on this article by Zettlemoyer, 241: 5–6. [ABSTRACT FROM AUTHOR]

Background and aims: Soil properties and climate influence leaf chemical traits producing intraspecific variation in plants. Studies evaluating their importance in the South American Temperate Forest (STF) species are scarce. This study aimed to evaluate the intraspecific differences in five evergreen species of the rainforest considering two contrasting areas (i.e. temperature and precipitation), linking soil and climate with plants traits. Methods: Soil properties (Corg%, N%, C/N, δ13C, δ15N, pH and temperature), climate variables (mean annual precipitation and temperature [MAP; MAT]) and leaf chemical traits (C%, N% and P%, C/N, N/P, δ13C and δ15N) were measured and compared between two areas in the Northern Patagonia (42°- 44°S). In addition, the relationship of leaf chemical traits with soil and climate was assessed. Results: Significant differences were found in soil (Corg%, C/N and pH; p < 0.05) and climate (p < 0.05), with MAP identified as the most common factor controlling soil properties (Corg%, C/N and δ15N). Intraspecific differences in leaf chemical traits were found between areas, but not in all traits. The most common leaf chemical trait with significant differences was C%. Higher mean C% values were found in the island in plants and soils. High number of correlations (n = 13 correlations; p < 0.05) were found between leaf chemical traits. On the other hand, only MAP was a significant predictor of δ13C in the leaves. Conclusion: The leaf chemical traits variability suggests a species-specific response to the soil and climate conditions, with important influence of precipitation as the most common predictor of soil properties and δ13C in the leaves. [ABSTRACT FROM AUTHOR]

Soil water extracts could help to quickly assess the potential hazard of contaminants in soil, groundwater, and surrounding receiving water. In this study, the adverse effects of water extracts obtained from soils contaminated by heavy metals (sites A and B) or hydrocarbons (sites C, D and E) were evaluated using wheat, pak choi, and zebrafish. The test results obtained with freeze-dried soil samples showed a good correlation with those obtained from fresh wet soil samples. Phytotoxicity level was found to be greater in samples obtained from the metal-contaminated site B as compared to those from site A, whereas the opposite was observed for the zebrafish embryo acute toxicity. The water-soluble fractions of petroleum hydrocarbons in soils from sites C and D pose ecological risks to the environment, even though the concentrations of total petroleum hydrocarbon were below the established screening value. The results obtained with our battery of biological assays could complement the ecological risk estimation of a complex mixture of contaminants in soils. Site-specific ecological risk assessment using chemical analytical data, screening values, and ecotoxicity testing with soil water extracts could serve as a screening approach to identify the impact of contaminated soils on the freshwater environment. [ABSTRACT FROM AUTHOR]

Phosphogypsum is classified into naturally occurring radioactive materials containing radionuclides such as 238U, 226Ra and 232Th, and heavy metals which are dispersed in different form and concentrations and can be dangerous for humans. Determination of the concentration of radionuclides in soils and plants near a phosphate fertilizer production unit and phosphogypsum stacks was carried out by γ- and α-spectroscopy while trace elements were determined by Neutron Activation Analysis and Atomic Absorption Spectroscopy. Transfer and enrichment factors were estimated as well as radiation risks and the results led to the conclusion that the radiation hazard in the investigated region was below than the recommended level. [ABSTRACT FROM AUTHOR]

In recent years, the root microbiome (i.e., microorganisms growing inside, on, or in close proximity to plant roots) has been shown to play an important role in plant health and productivity. Despite its importance, the root microbiome is challenging to study because of its complexity, heterogeneity, and subterranean location. Fortunately, root microbiome research has seen a tremendous influx of novel technologies (e.g., imaging tools, robotics, and molecular analyses), experimental platforms (e.g., micro- and mesocosms), and data integration, modeling, and prediction tools in the past decade that have greatly increased our ability to dissect the complex network of interactions between above- and belowground environmental parameters, plants, bacteria, and fungi that dictate soil and broader ecosystem health. Herein, we discuss methods that are currently used in root microbiome research and that can be expanded to phytobiome research in general ranging from laboratory studies to mesocosm-scale studies and, finally, to field studies; evaluate their relevance to ecosystem studies; and discuss future root microbiome research directions.

Blue carbon ecosystems (BCEs), located at the land-sea interface, provide critical ecological services including the buffering of anthropogenic pollutants. Understanding the interactions between trace element (TE) loads in BCEs and socioeconomic development is imperative to informing management plans to address pollution issues. However, the identification of anthropogenic TE pollution in BCEs remains uncertain due to the complex geochemical and depositional processes and asynchronous socioeconomic development along continental coastlines. Here, priority-controlled TE (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) concentrations in the mangrove, saltmarsh and seagrass soils and plant tissues along the coastline of China were investigated while taking bare flat and upland soils as corresponding references. We demonstrate that blue carbon (BC) soils accumulated markedly higher concentrations of anthropogenic TEs than the reference soils, mainly due to the effective trapping of fine-grained particles and higher binding capacities. We identify the time course of TE changes over the last 100 years which shows increasing anthropogenic TE accumulation resulting from military activities (1930–1950) and the growth of industrial and agricultural activities (1950–1980), then reaching a maximum after national economic reform (1980–2000). Since the 2000s, decreases in TE discharges driven by socioeconomic reform and strengthened environmental regulations have led to a widespread reversal of anthropogenic TE concentrations in BC soils. Based on the current TE flux we estimate that BCEs can filter over 27.3–100 % of the TEs emitted in industrial wastewaters from Chinese coastal provinces annually. However, the uptake of these TEs by plants can be substantially reduced through various mechanisms offered by edaphic properties such as organic carbon, clay, and sulfur contents. Therefore, enhancing TE filtering while preventing TEs from entering food webs through the conservation and restoration of BCEs will greatly aid in achieving the sustainable development goal of the coastal zone under intensified anthropogenic activities.

Long-term vegetation cover can affect soil organic carbon content and carbon flow within the soil food web. Nematode trophic structure and soil properties were evaluated in pear rows (intra) maintained without weeds applying herbicide and in the inter-rows (between rows) covered with: Medicago+grasses (MG), fescue or spontaneous vegetation. Soil samples were taken at 0-20 and 20-40 cm depths from 2012 to 2014. Nematode assemblage was different in each inter-row and row, mainly in the topsoil. The inter-rows were reservoirs of omnivores-predators. The MG inter-row promoted the highest accumulation of organic carbon, total N and exchangeable K in the soil. The enrichment index was related to the quantity of dry matter produced by cover crops with the highest index observed in MG. Nematode biomass showed a positive correlation with intra and inter-rows soil organic carbon. Carbon flow through bacterivores prevailed in intra-rows, while bacterivores or herbivores canalized the inter-rows. [ABSTRACT FROM AUTHOR]

This study is devoted to heavy metal soil migration to coltsfoot in urban pollution of Tyumen city. Soil and plant samples were collected in the summer of 2017 to 2020 at the control site, highway, engine-building, oil refinery, battery manufacturing, and metallurgical plants. Heavy metals (Cu, Zn, Fe, Mn, Pb, Cd, Ni, Co, and Cr) mobile and acid-soluble forms in soils, and metals concentration in plants were analyzed by atomic absorption and atomic emission spectroscopy. Metals concentration in soils of urban area exceeded the control by 1.1 to 20 times. Relative accumulation of metals decreased in the order: Pb > Cu > Zn > Ni > Cr > Fe > Co > Mn > Cd. Heavy metals mobility in soils decreased in the order: Cd > Mn > Pb > Zn > Ni = Cu > Co > Cr > Fe. Coltsfoot metal accumulation changed in the order: Fe > Zn = Mn > Pb > Cu > Cr > Co > Ni > Cd. The highest contamination for most of the metals was at the metallurgical plant, while Ni and Co concentrations were maximum at the oil refinery. Content of Cu, Zn, Fe, Cd, Ni, and Co in coltsfoot correlated with a concentration in soils. Bioconcentration factor showed the following metal bioavailability: Cu > Zn > Cd > Pb > Ni > Mn > Cr > Co > Fe. Heavy metal accumulation in coltsfoot should be taken into account during sanitary control of herb drugs based on this plant. [ABSTRACT FROM AUTHOR]

The relevance. The steady growth in the world of geochemical and ecological studies of mercury in local-regional-planetary plans is associated with the active circulation and omnipresence of its various forms in terrestrial and aquatic environments of bisophere, as well as with its supertoxicity and high biodestructivity. The relevance of this study determines the use of modern tools for highly sensitive analysis in the biogeochemical study of different types of components of the plant-bedding-soil system at three landfills of protected mining areas in the south of the Far East. The main aim of the research is to establish mercury content in the vegetation and soils of Primorsky Krai. Objects: soils, vegetation fallout, forest litter, plants of Primorsky Krai. Methods. Content of the mass fraction of total mercury was determined in International Research Centre «Uranium geology» (TPU) without preliminary chemical decomposition of samples by flame-free atomic absorption spectrometry. Mercury analyzer RA-915+ with pyrolytic prefix RP-91C (Lumex LLC, St. Petersburg) was used. Results. The obtained results characterize the mercury content of adjacent soils, vegetation fallout and vegetation in a combination of three naturally separate sections of the Sikhote-Alin ridge, which are located within the protected, potentially geochemical «primary» natural territories of the Primorsky Krai. The average mercury content for soils in the vicinity of the Vanchin-Ugolny stream, Shandui lakes and the tributary of the Bikin river was, respectively (mg/kg): 0,162 (range 0,046–0,298), 0,098 (range 0,015–0,264) and 0,117 (range 0,021–0,28). Differences in mercury content in the soils of the studied areas depend on the amount of organogenic component and landscape characteristics of the area. Mercury content in different types of vegetation was: lichen (0,135 mg/kg), fern (0,0383 mg/kg), labaznik (0,023 mg/kg), sedge (0,016 mg/kg), which is explained by the different ability of plants to physiologically and biologically fix water-soluble forms of mercury. Higher mercury content in soils compared to plant litter and vegetation itself is the evidence of long-term accumulation of reserves of this metal and binding of its main mass in organomineral form in soils.

Radioecological features of natural environments of the Sochi River valley, one of the largest rivers of the Main Caucasian Range and the Black Sea coast of Russia were studied. Alluvial soils, mosses, and river waters were the subject of investigations. Peculiarities of Th and U behavior (their contents were determined by quantitative ICP method) in conditions of existence of alkaline geochemical barriers — calcium barrier formed at the junction of neutral argillites and alkaline marl, and sodium barrier in the river mouth at the contact of river water with sea water were established. The calcium barrier results in lower Th and U concentrations in river waters and higher concentrations of radioactive elements in soils and mosses. Alkaline sodium barrier causes increase of Th and U concentration in river waters, decrease of Th and U concentration in soils and active sorption of elements by mosses. On the whole, the radioecological state of the Sochi River valley is favorable. The level of gamma-radiation exposure dose rate near the surface is lower than the natural level of this parameter for the open mountain territories of the middle belt of Russia. Bottom sediments of the river are notable for low values of specific activity of natural radionuclides 226Ra, 228Ra, 224Ra, 232Th and 40K.

The man-made activity of mankind has led to the emergence of many global problems and caused the deterioration of the quality of the natural environment (air, water, soil). Of particular concern is the contamination of agricultural land with toxicants, in particular, radionuclides, which, entering the soil – plant – human body food chain, can reach toxic levels. Therefore, an important task is the removal of hazardous substances from the soil. Phytoremediation can be one of the effective methods for reducing its pollution. The article examines the effectiveness of phytoremediation of soils contaminated as a result of the accident at the Chernobyl nuclear power plant in certain territories of Polissia of Ukraine (Korosten district of Zhytomyr region). Nectar-pollinating plants were selected for the research, which was carried out for two years: great globe-thistle (Echinops sphaerocephalus), milk thistle (Silybum marianum), and white melilot (Melilotus albus). The results of the research showed that in the dry vegetative mass of milk thistle, great globe-thistle, and white melilot, the specific activity of 137Cs over the two years of research was in the range from 30.8 Bq/kg to 238.5 Bq/kg, the accumulation coefficient – from 0.135 to 0.985, and the hazard coefficient – from 0.055 to 0.395. The highest indicators of specific activity and accumulation coefficient of 137Cs were observed in the vegetative mass of the white melilot, which amounted to 238.5 Bq/kg and 0.96, respectively, comparatively lower values – 2.3 times and 2.3 times were found in the vegetative mass of milk thistle, 2.8 times and 7.1 times – in the vegetative mass of the great globe-thistle. At this level of accumulation of 137Cs in the vegetative mass of nectarine plants from the soil, on average, over two years of research, 1130550 Bq of this radionuclide was removed from the soil per hectare of agricultural land with milk thistle, 621250 Bq with great globe-thistle, and 2851650 Bq with white melilot. The removal of 137Cs with the vegetative mass of nectarine plants reduced the content of this radionuclide in the soil per 1 kg – from 3.4% to 8% on average over two years of research. [ABSTRACT FROM AUTHOR]

Taking into consideration, the challenges faced by the environment and agro-ecosystem make increased for suggestions more reliable methods to help increase food security and deal with difficult environmental problems. Environmental factors play a critical role in the growth, development, and productivity of crop plants. Unfavorable changes in these factors, such as abiotic stresses, can result in plant growth deficiencies, yield reductions, long-lasting damage, and even death of the plants. In reflection of this, cyanobacteria are now considered important microorganisms that can improve the fertility of soils and the productivity of crop plants due to their different features like photosynthesis, great biomass yield, ability to fix the atmospheric N2, capability to grow on non-arable lands, and varied water sources. Furthermore, numerous cyanobacteria consist of biologically active substances like pigments, amino acids, polysaccharides, phytohormones, and vitamins that support plant growth enhancement. Many studies have exposed the probable role of these compounds in the alleviation of abiotic stress in crop plants and have concluded with evidence of physiological, biochemical, and molecular mechanisms that confirm that cyanobacteria can decrease the stress and induce plant growth. This review discussed the promising effects of cyanobacteria and their possible mode of action to control the growth and development of crop plants as an effective method to overcome different stresses. [ABSTRACT FROM AUTHOR]

The accumulation of six pharmaceuticals of different therapeutic uses has been thoroughly investigated and compared between onion, spinach, and radish plants grown in six soil types. While neutral molecules (e.g., carbamazepine (CAR) and some of its metabolites) were efficiently accumulated and easily translocated to the plant leaves (onion > radish > spinach), the same for ionic (both anionic and cationic) molecules seems to be minor to moderate. The maximum accumulation of CAR crosses 38,000 (onion), 42,000 (radish), and 7000 (spinach) ng g−1 (dry weight) respectively, in which the most majority of them happened within the plant leaves. Among the metabolites, the accumulation of carbamazepine 10,11-epoxide (EPC — a primary CAR metabolite) was approximately 19,000 (onion), 7000 (radish), and 6000 (spinach) ng g−1 (dry weight) respectively. This trend was considerably similar even when all these pharmaceuticals applied together. The accumulation of most other molecules (e.g., citalopram, clindamycin, clindamycin sulfoxide, fexofenadine, irbesartan, and sulfamethoxazole) was restricted to plant roots, except for certain cases (e.g., clindamycin and clindamycin sulfoxide in onion leaves). Our results clearly demonstrated the potential role of this accumulation process on the entrance of pharmaceuticals/metabolites into the food chain, which eventually becomes a threat to associated living biota. [ABSTRACT FROM AUTHOR]

Nowadays, there are a multitude of sources of heavy metal pollution which have unwanted effects on this super organism, the soil, which is capable of self-regulation, but limited. Living a healthy life through the consumption of fruits and vegetables, mushrooms, edible products and by-products of animal origin, honey and bee products can sometimes turn out to be just a myth due to the contamination of the soil with heavy metals whose values, even if they are below accepted limits, are taken up by plants, reach the food chain and in the long term unbalance the homeostasis of the human organism. Plants, these miracles of nature, some with the natural ability to grow on polluted soils, others needing a little help by adding chelators or amendments, can participate in the soil detoxification of heavy metals through phytoextraction and phytostabilization. The success of soil decontamination must take into account the collaboration of earth sciences, pedology, pedochemistry, plant physiology, climatology, the characteristics of heavy metals and how they are absorbed in plants, and in addition how to avoid the contamination of other systems, water or air. The present work materialized after extensive bibliographic study in which the results obtained by the cited authors were compiled. [ABSTRACT FROM AUTHOR]

A brief description of the agrochemical properties of the soils that make up the dumps of overburden rocks of quarries, sludge storage facilities of processing plants and waste rocks of mines is given. It was noted that the soils in the dumps and sludge dumps are represented predominantly by rocks of deep horizons, contain trace elements of many metals and have absolutely no organic components, nitrogen and phosphorus. A substantiation of plant species for biological reclamation (greening) of man-made objects consisting of iron ore mining and enrichment waste has been carried out. It is recommended to plant seedlings of poplars (Pópulus), maples (Acer), acacia (Robinia), pine (Pinus) as well as oleaster shrubs (Elaeagnus) and amorpha (Amorpha) directly on the rock with local excavation of holes on horizontal and slightly inclined areas of dumps. Landscaping of steep slopes (30-40°) and the surface of sludge storage facilities is proposed to be carried out by stimulating natural self-overgrowth by applying (including by hydraulic method) a mixture of seeds of perennial grasses, trees and shrubs along with mineral fertilizers and humus of organic substances. The surface of sludge storages, due to the high degree of salinity and "cementation" of the substrate, before planting plants, requires obligatory soiling with a layer of at least 200 mm of chernozem or a mixture of chernozem with loam, followed by planting of xerophyte plants: meadow brome (Lolium pratense), straight brome (Bromus erectus Huds)), rye - triticale (Triticosecale). [ABSTRACT FROM AUTHOR]

Since natural bioremediation is a lengthy process, new bioremediation techniques should be developed to accelerate and optimize the removal of soil contaminants such as polycyclic aromatic hydrocarbons (PAHs). One of the substances that can be used to enhance PAH removal is calcium peroxide, applied as an oxidizing agent to improve soil aeration. Here, we investigated the bioremediation of soil contaminated with fluoranthene. Two doses of calcium preparation (CP), 0.29 and 0.58 g/kg, composed of calcium peroxide and calcium hydroxide, and increasing the soil pH by one and two units, respectively, were used. Fluoranthene decline was 83% and 95% for CP-aided soils, and 80% for soil without calcium preparation. During the remediation process, dynamic changes in the sorption complex of soils were found, mainly due to changes in the sum of base exchangeable cations. These changes in the first experiment period were significantly influenced by the presence of calcium preparation while in the second period by the presence of fluoranthene. The presence of calcium preparation caused changes in the microbiocenosis, especially at the higher dose. There was no effect of calcium preparation on plant growth. [ABSTRACT FROM AUTHOR]

Vegetables cultivated near roads absorb toxic metals from polluted soil, which enter the human body through the food chain and cause serious health problems to humans. The present study investigated the concentration of lead (Pb) and nickel (Ni) in soils and vegetables grown along the roadside of District Swat, Pakistan, and the health risks associated with the consumption of the tested vegetables. In results, Pb concentration was higher in plants located at the distance between 0–10 m away from the roadside than the WHO permissible limit. In such plants, Pb concentration was higher than Ni. Rumex dentatus contained the highest concentration of Pb (75.63 mg kg−1 DW) among the tested vegetables while Ni concentration (27.57 mg kg−1 DW) was highest in Trachyspermum ammi as compared to other plants. Concentration and accumulation of both the metals decreased in soil and plants with increasing distance from the road. Similarly, target hazard quotient values noted for Pb (up to 3.37) were greater than unity, which shows that there is a potential risk associated with the consumption of tested vegetables near the road. Moreover, the values of target cancer risk (up to 0.8413) were greater than 0.0001, which shows that there is a risk of cancer with the consumption of tested vegetables. In conclusion, the consumption of tested vegetables was very dangerous as it may lead to higher risks of cancer. Strict regulatory control is recommended on the cultivation of these vegetables along the roadside to avoid any contamination due to roadside exhaust. [ABSTRACT FROM AUTHOR]

Grazing by domestic animals is an economic activity that can alter the ecosystem structure and functioning of drylands. Some rangelands are experiencing a temporary or complete abandonment of grazing, but the effects of these practices on the ecology of drylands are poorly studied. Plant patches are recognized as fertility islands in drylands. Unvegetated inter-patches, far from being lifeless, harbor diverse soil microbial communities, habitually in the form of biocrusts. Here, we determined changes in plant, biocrust, and bare soil cover after grazing cessation over a 63-year period in Patagonian semiarid drylands. We also quantified, at microsite (2.25 m2) and plot (2500 m2) scales, temporal changes in soil multifunctionality by using four specific soil multifunctionality indexes associated with soil carbon, fertility, biogeochemical cycling, and stability. Our results indicate that biocrusts, although with low cover values, colonize new soil areas following grazing cessation, whereas bare soil cover increases at the expense of plants. We found that soil multifunctionality consistently increased with time since grazing cessation at the microsite scale, with biocrusts showing the highest multifunctionality values. We also observed that soil multifunctionality increased over time after grazing cessation at the plot scale, with bare soil and plants being more important than biocrusts due to their greater cover. Overall, our field study shows that the abandonment of grazing leads to a natural recovery of soil functioning in semiarid rangelands, with biocrusts and microbial communities of bare soils playing central roles, but at different spatial scales. • Biocrust and bare soil cover increase but plant cover decreases after 63 years of grazing cessation. • Biocrusts show higher soil multifunctionality than plants or soils at a microsite scale. • Bare soil and plants contribute the most to soil multifunctionality at a plot scale. • Multifunctionality increases with time since grazing abandonment in all microsites. • All microsites provide soil multifunctionality as a spatial continuum in drylands. [ABSTRACT FROM AUTHOR]

The Mg isotope system helps constrain a variety of geochemical processes in the hydrosphere, lithosphere and biosphere. DSM3 is commonly used as delta‐zero material for relative Mg isotopic measurements. In this study, we have characterised the Mg isotopic composition of a new pure Mg solution (Alfa‐Mg). This solution could potentially be used as a secondary delta‐zero reference material, or as an alternative primary reference material when DSM3 is depleted. The Alfa‐Mg solution has been checked for homogeneity and stability and is available free of charge upon request. The certified δ26/24Mg value relative to DSM3 of the Alfa‐Mg solution is −1.40‰, with an expanded (k = 2) uncertainty of 0.05‰. We also characterised a range of existing Earth‐surface reference materials including soils, riverine sediments and plants. The δ26/24Mg values (relative to DSM‐3) of plant materials range between −1.06 ± 0.03‰ (2s, n = 12) and −0.75 ± 0.03‰ (2s, n = 12). The δ26/24Mg values of soil materials vary from −0.72 ± 0.11‰ (2s, n = 12) to 0.17 ± 0.05‰ (2s, n = 12). The δ26/24Mg values of riverine sediment materials range between −0.66 ± 0.01‰ (2s, n = 12) and −0.17 ± 0.03‰ (2s, n = 12). These data could serve as a reference for inter‐laboratory calibration and quality control, as well as for potential applications in geological and biological fields. [ABSTRACT FROM AUTHOR]

Soil is a living heterogeneous body mass consists of solid, water, gases, organic, inorganic matters and organisms and acts upon as a source and sink of any contaminant. Nanotechnology is a diversified, dynamic and transformative technology, which stimulates the scientific innovation for the betterment of different sectors of the society which produces large number of nanocontaminants. Nanocontaminants in the soil are a major concern because of their toxicities with subsequent threat to soil, environment and human community. These contaminants may badly influence soil ecology, crop production, or product quality, ground water purity and human health. Moreover, the safety protocol for the specific nanocontaminants is yet to be developed to protect our environment and ecology. Of late many research experiments were conducted to investigate and comprehend the outcome, lethal dose and behaviour of nanocontaminants and consequently to extend this knowledge for development of bio-safety protocol to handle the nanocontaminants in the coming decade. Research initiatives are focused on to understand the impacts of manufactured nanoparticles on human being, soil and formulate combat mechanisms to mitigate the adverse consequences of nanocontaminants on human health and soil quality. While this attempt signifies an exclusive chance for soil scientists to investigate these highly potential technologies, it also emphasizes on foremost challenges to a field of research that has great scope to predict the consequences of nanocontaminants on the soil ecology and animal health. Currently nanocontaminants draw the major world research attention and need more endeavours to entirely assess their impacts. This review documented an outline of impacts of nanocontaminants in soil, which highlights the understanding of major interactive effects of nanocontaminants on soil organisms, plants, and human. This article also provides highlights of the challenges that soil researchers and policy makers face when developing risk assessment tool for nanocontaminants in soil and subsequently for human being. [ABSTRACT FROM AUTHOR]

An effective toxicological assessment of soil-metal bioavailability and plant translocation processes is needed in view of the growing negative impact of trace element pollution on the terrestrial environment and human health. This study was conducted to assess the toxicological processes that regulate the plants' trace element absorption into their tissues, the suitability for human use, the potential sources of trace elements, and the risk to human health, using an integrated research methodology. Soils and sweet potato plants were collected from agricultural fields near the tannery waste disposal sites of Dhaka City, Bangladesh and inductively coupled plasma mass spectrometers (ICP-MS) were used to analyze the essential and toxic elements. The mean concentrations of total elements in soil followed the descending order of Fe > Zn > Mn > Cr > Ni > Pb > Cu > As > Cd and in plant Fe > Zn > Cu > Cr > Ni > Mn > Pb > As > Cd. In the edible tissues of sweet potato, the concentrations of essential and toxic elements exceeded the maximum permissible levels, indicating not safe for human consumption. The translocation factor (TF) revealed that studied elements are more accumulated in the leaves than tubers. The enrichment factor revealed minimal to very high enrichment of essential and toxic elements in the plant parts while the contamination factor showed low to very high contamination. Considering the health risk of toxic elements from plant samples, As and Pb caused non-cancer and cancer risk on human health. However, the present results suggested that regular monitoring of these essential and toxic elements in soil and plants as well as other food materials around the abandoned tannery waste disposal sites are necessary to prevent excessive build-up of these elements in the food chain. [ABSTRACT FROM AUTHOR]

Background: Isolated trees are often planted in agricultural landscapes around the world, but their planting background often remains unclear. In this study, we examined the history of demarcation trees in Ibaraki Prefecture in eastern Japan by using land dispute records mainly from the early modern period (from 1600 to 1868), the Rapid Survey Map (RSM) drawn in the late nineteenth century, demarcation tree records from 2011, and interviews of the local residents. Methods: We reviewed 39 documents on land disputes to examine the temporal and spatial usage of demarcation tree species in the early modern period. The association between the present distribution of 1486 individuals of six demarcation tree species and past land use in the RSM were analyzed with Fisher's exact test and residual analysis. In addition, we conducted interviews with 48 farmers, most of whom were over 60 years old. Results: The demarcation plants in vast communal lands and village boundaries in the early modern period were mostly visually prominent tall trees, usually pines. In contrast, smaller trees were planted for demarcation in small-scale areas of forests and farmlands. Although Pourthiaea villosa (Thunb.) DC. Has been planted since the mid-eighteenth century, its planting seems to have accelerated as communal forests were divided mainly in the Meiji period (from 1868 to 1912). The present dominant state of Deutzia crenata Siebold et Zucc. in older farmlands and its ritual use, history of upland field development in the Kanto region, and ancient demarcation use in central Japan indicate its original use may date back to the medieval (from 1185 to 1600) or ancient ritsuryo period (from the seventh century to 1185). Tea (Camellia sinensis (L.) Kuntze) and mulberry (Morus spp.) individuals were considered as early modern or modern crop remnants. Results from the map-based analysis and interviews clarified the recent increase in the use of Euonymus japonicus Thunb. and Celtis sinensis Pers. for demarcation. Conclusions: Chronologically dynamic anthropogenic legacies have shaped the present agricultural landscape with different demarcation tree species. A better understanding of the dynamic transformation of vegetation under human influence adds to the historical heritage value of the landscape and should motivate its conservation. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The geochemical regional specialization of the behavior of rare earth elements (REE) in the soils of Sochi, manifested in the predominance of REE of the middle group, has been established. The enrichment by the middle group of REE is inherited from the rocks (mainly clayey mudstones) of the territory. At the same time, the features of the distribution of REE, characteristic of natural soils, are not violated for soils formed under the conditions of technogenesis. This indicates that the pollution of urban soils is determined by a natural and technogenic factor. The sources of pollution are man-made sites and talus, which lack a soil-vegetation layer, including those recently formed during the preparation for the 2014 Winter Olympic Games and composed of the same material as the parent rocks, but significantly crushed and, accordingly, subject to active weathering. In mosses of the urban zone, in the eluvial landscape, the predominance of the middle group of REE is not observed. However, as we move down the slope, the REE distribution curve relative to the North American shale standardization becomes similar to the similar graph for soils and rocks. The relationship between the accumulation of elements in mosses, and in soils and underlying rocks is revealed when considering the features of fractionation of REE in mosses of the super-aquatic landscape.

Mercury (Hg) is an integral part of Earth's biogeochemical cycles, yet anthropogenic activities significantly elevate its environmental presence, posing considerable ecological and human health risks. Human exposure primarily arises from the consumption of Hg-contaminated freshwater and marine fish. The Minamata Convention on Mercury, initiated by the United Nations Environment Programme (UNEP), aims to mitigate global Hg emissions, reinforced by comprehensive monitoring efforts. The biogeochemical cycling of Hg is complex, encompassing intricate processes of distribution, transformation, and bioaccumulation that connect sources to exposure pathways. Thus, evaluating Hg biogeochemical behavior and potential environmental hazards is crucial in the global scientific fraternity. Although global policies address direct Hg emissions, comprehending its biogeochemical cycling remains challenging and continues to spur scientific investigation. Coal combustion is a significant source, accounting for approximately 60 % of Hg emissions, especially in geologically predisposed regions, with atmospheric deposition being a key factor, leading to elevated Hg levels in terrestrial soils. Health risks associated with Hg exposure are more acute in soil-contaminated environments than in aquatic systems, with ingestion posing greater risks than dermal contact. This review focuses on the biogeochemical cycling of Hg in the natural environment, highlighting contamination patterns and providing updated insights into Hg's impact on aquatic and terrestrial ecosystems. • Biogeochemical cycling of mercury (Hg) in the environment has been elucidated. • Uptake of Hg in plants was elaborated. • Health risks were more pronounced in soil-contaminated regions compared to water samples. • Ingestion pathways posing greater risks than dermal exposure. [ABSTRACT FROM AUTHOR]

The use of biochar in soil remediation is a promising method to deal with metal contamination. In the present study, the influence of biochar amendment on the toxicity of silver (as AgNO3) to terrestrial organisms was assessed. For this, toxicity tests were conducted with terrestrial plant barley (Hordeum vulgare) and invertebrate springtails (Folsomia candida) in the standard natural Lufa soil amended or not with a wood-derived biochar at 5% (w/w). Biochar addition increased root length and mass in barley, compared to unamended soil. However, the effects of Ag on barley growth were masked by a great variation among replicates in biochar-amended soil. Photosynthetic pigment contents (total chlorophyll and carotenoids) were lower in plants exposed to Ag in Lufa soil, but not in biochar-amended soil. Moreover, Ag drastically decreased dehydrogenase activity in Lufa soil. For springtails, the addition of biochar clearly decreased the toxicity of Ag. The LC50 was 320 mg Ag/kg in Lufa soil, while no mortality was observed up to 500 mg Ag/kg in biochar-amended soil. The EC50 for effects on reproduction was significantly higher in biochar-amended soil compared to unamended Lufa soil (315 and 215 mg Ag/kg, respectively). The wood-derived biochar used in this study has shown a potential for remediation of contaminated soils, as a decrease in Ag toxicity was observed in most endpoints analysed in barley and springtails. [ABSTRACT FROM AUTHOR]

Copyright of Arab Gulf Journal of Scientific Research is the property of Arabian Gulf University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article considers vulnerable communities in climate mitigation and adaption plans in India. Emphasis is given on the importance of solar and other renewable energy as a solution to climate change. It discusses the link of afforestation to climate change and carbon dioxide mitigation, as well as a part of watershed development projects to improve soil and moisture conservation. It sees the extension of coast embankments as maladaptive since it disrupted sediment flow and increased erosion.

Identifying patterns and drivers of plant community assembly has long been a central issue in ecology. Many studies have explored the above questions using a trait‐based approach; however, there are still unknowns around how patterns of plant functional traits vary with environmental gradients. In this study, the responses of individual and multivariate trait dispersions of 134 species to soil resource availability were examined based on correlational analysis and torus‐translation tests across four spatial scales in a subtropical forest, China. Results indicated that different degrees of soil resource availability had different effects on trait dispersions. Specifically, limited resource (available phosphorus) showed negative relationships with trait dispersions, non‐limited resource (available potassium) showed positive relationships with trait dispersions, and saturated resource (available nitrogen) had no effect on trait dispersions. Moreover, compared with the stem (wood density) and architectural trait (maximum height), we found that leaf functional traits can well reflect the response of plants to nutrient gradients. Lastly, the spatial scale only affected the magnitude but not the direction of the correlations between trait dispersions and environmental gradients. Overall, the results highlight the importance of soil resource availability and spatial scale in understanding how plant functional traits respond to environmental gradients. [ABSTRACT FROM AUTHOR]

Biochar has attracted interest due to its ability to improve soil fertility, soil carbon, and crop yield. Also, biochar can adsorb metals and render them less bioavailable. We investigated the soil availability, sequential extraction, and maize uptake of Cd, Pb, and Zn in a highly contaminated soil amended with rice straw biochar rates (0.0, 5.0, 10.0, 20.0, and 30.0 Mg ha−1). We hypothesized that biochar application to the soil cultivated with maize attenuates metal toxicity and mobility in slag-polluted soils near an abandoned Pb smelting plant in Brazil. Results showed that applying biochar increased the soil organic carbon, CEC, and P up to 27, 30, and 107, respectively. Plant accumulation of P and N was 104 and 32% higher than control, while aerial and root biomasses were increased by 18 and 23%. The sequential extraction showed that Pb and Zn in the original soil were retained mainly in residual fractions (94 and 87%, respectively), while Cd was mostly allocated in the organic fraction (47%). Biochar rates increased the proportion of Cd in the organic fraction to 85%, while Pb and Zn were redistributed mainly into iron oxides. The Cd, Pb, and Zn bioavailability assessed by DTPA decreased 32% in the biochar-amended soil, reducing plants' metal uptake. The maize biomass increase, metal soil bioavailability decrease, and low metal concentration in shoots driven by biochar indicate that phytoattenuation using rice straw biochar and maize cultivation could reduce risks to humans and the environment in the polluted sites of Santo Amaro. [ABSTRACT FROM AUTHOR]