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Earthworms modulate carbon and nitrogen cycling in terrestrial ecosystems, but their effect may be compromised by the deposition of pollutants from industrial emissions. However, studies investigating how deposited compounds affect the role of earthworms in carbon cycling such as litter decomposition are lacking, although the interactions of earthworms and deposited compounds are important for understanding the impact of pollutants on ecosystems and the potential of earthworms in bioremediation. We performed a 365‐day in situ litterbag decomposition experiment in a deciduous (Quercus variabilis) and coniferous (Pinus massoniana) forest in southeast China. We manipulated nitrogen (N), sodium (Na), and polycyclic aromatic hydrocarbons (PAHs) as model compounds during litter decomposition with and without earthworms (Eisenia fetida). After one year, N, Na, and PAH all slowed down litter mass loss, with the effects of Na being the strongest. By contrast, E. fetida generally increased litter mass loss, and the positive effects were uniformly maintained irrespective of the type of compounds added. However, the pathways to how earthworms increased litter mass loss varied among the compounds added and the two forests studied. As indicated by structural equation modeling, earthworms mitigated the negative effects of deposited compounds by directly increasing litter mass loss and indirectly increasing soil pH and microbial biomass. Overall, the results indicate that the acceleration of litter mass loss by earthworms is little affected by deposited compounds, and that earthworms have the potential to mitigate negative impacts of pollutants on litter decomposition and ecosystem processes. [ABSTRACT FROM AUTHOR]

• Significant differences in the responses of hydrodynamics, water quality and aquatic habitats to connectivity changes. • The connectivity threshold under multi-targets determined based on the water environment response is more accurate. • The optimal connectivity threshold is of great significance for solving wetland environment ecological degradation. The quality of the water environment of wetlands is closely related to the changes in hydrologic connectivity, so wetland responses to changing connectivity exhibit a range of optimal connectivity values. Identifying these ranges of values is of great significance for wetland ecological restoration. Current studies mostly determine the hydrologic connectivity ranges based on a single target, even though connectivity simultaneously affects multiple water environment targets. Hence, the optimal hydrologic connectivity should be determined by accounting for multiple targets. With the Baiyangdian Wetland as the study area, we developed a method to model how the water environment responded to changes in hydrologic connectivity from three perspectives: hydrodynamics, water quality, and aquatic habitat. To do so, we used the BP neural network model and a non-dominated sorting genetic algorithm to calculate the hydrologic connectivity values in a context with multiple targets. We found that under the optimal hydrodynamic target, the integral index of connectivity (IIC) threshold was [0.23, 0.61] and the probability connectivity (PC) threshold was [0.32, 0.68]; under the optimal water quality target, the IIC threshold was [0.42, 0.70] and the PC threshold was [0.48, 0.82]; under the optimal aquatic habitat target, the IIC threshold was [0.38, 0.69] and the PC threshold was [0.35, 0.71]; and under the comprehensive optimization target, the IIC threshold was [0.48, 0.64] and the PC threshold was [0.51, 0.73]. These ranges of values will help wetland managers determine the optimal ecological water releases to meet the ecosystem quality targets. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on Hemiphragma heterophyllum led to the isolation of two new compounds, heterophyllumin A (1) and heterophylliol (3), along with nine known compounds, (‒)-sibiricumin A (2), iridolactone (4), jatamanin A (5), dihydrocatalpolgenin (6), 25-hydroperoxycycloart-23-en-3β-ol (7), 24-methylenecycloartanol (8), (+)-pinoresinol (9), hexadec-(4Z)-enoic acid (10), and 9,12, 15-octadecatrienoic acid (11). Their structures were elucidated on the basis of detailed spectroscopic analyses and by comparison with literature data. Further, the structure of compound 3 was unambiguously confirmed by single-crystal X-ray analysis. Some of those compounds showed moderate activity in the α-glucosidase inhibition assay. [ABSTRACT FROM AUTHOR]

To identify status, source of polycyclic aromatic hydrocarbons (PAHs) in urban soils and to assess soil environmental quality in Xi’an City, China, total 45 soil samples were collected from surface layer (0-10 cm) in different functional areas. Total concentrations of 16 US EPA priority PAHs ranged from 149.9 to 5770 μg kg−1, with a mean of 1246 μg kg−1. High molecular weight (HMW) PAHs accounted for the majority (42.4-72.2%) of the total PAHs in the urban soils, and phenanthrene (Phe), fluorene (Flo), pyrene (Pyr), benzo(b)fluoranthene (BbF), and chrysene (Chr) were the major compounds. Concentrations of PAHs varied among different functional areas. High level of PAHs was particularly apparent in industrial zones and city road overpass, while low level was recorded in scenic spots and campus. The integration of isomer ratios, principal component analysis (PCA), and positive matrix factor (PMF) indicated that the sources of PAHs in Xi’an urban soils were mainly derived from vehicle emissions and coal combustion. Based on incremental lifetime cancer risks (ILCR) model, the urban soils from the three functional areas (industrial zone, urban road, and city road overpass) posed potential cancer risk, and the cancer risks of direct ingestion for children were apparently higher than that for adolescence and for adult, respectively. Therefore, attention should be paid to the health risk for children exposed to PAHs in the urban soils. [ABSTRACT FROM AUTHOR]

Mould design for the restored model of Zhang Heng's seismometer is one of the important parts in restoration research, whose outside mould reflects the basic requirement of instrumental function and which is also a visual form of displaying to a certain degree the culture and art in Han dynasty. So the mould design of the restored model includes the two study aspects of structural mould and art mould. In this paper, some new results obtained from the relevant historical literatures and archaeological study are reviewed first, and then the three kinds of tube-, bell-, and egg-shaped moulds designed in existing models are discussed briefly. Based on the newly restored model turned out by the research group of China Earthquake Administration and State Cultural Relics Bureau, in addition to analyzing the corresponding design restoration of basic shape, the position of upper hanging point, adjusting structure and instrumental stability relating to structural mould, the paper also introduces the design idea, cultural succession and art expression relating to art mould. The purpose of design restoration of Zhang Heng's seismometer is for better displaying Zhang Heng's great historical contribution to the world. [ABSTRACT FROM AUTHOR]

Focuses on the values of senior women intellectuals in China. Description of senior women intellectuals; Cultural and psychological quality of Chinese women intellectuals; Value of afforded career and family; Factors considered by the women as social status determinants.

River system network (RSN) connectivity is important to maintain the environmental and ecological functions of wetlands. Quantitative evaluation of connectivity can provide crucial support for efforts to improve wetland connectivity and to restore and protect wetland ecosystems. Most existing evaluation methods uniformly generalise RSN to form an undifferentiated RSN of edges and nodes that is taken as a whole to evaluate the connectivity. However, actual RSNs comprise rivers, canals, ditches, lakes, and ponds, which differ substantially in their structures, morphologies, and attributes. The mix of RSN elements therefore defines grades that give RSNs distinctive characteristics. Moreover, RSNs with different grades perform different ranges of environmental and ecological functions. The existing evaluation methods, which have some limitations, do not account for these characteristics. To account for these differences, we examined the grade characteristics and their impact on environmental and ecological functions. We established a grading system of RSN elements and a grading method of RSN, and constructed the structural connectivity evaluation indicator system for RSNs at different grades. On this basis, we propose a method for grading evaluation of RSN connectivity. We used China's Baiyangdian Wetland to demonstrate the use of the system and validate the results. The proposed method provided an objective and accurate evaluation of RSN connectivity and clarified the differences in connectivity among RSNs with different grades, thereby providing improved guidance for the development and maintenance of the environmental and ecological functions of RSNs. [ABSTRACT FROM AUTHOR]

• Appropriate Na amendment facilitate leaf litter decomposition. • Na amendment increases similarity of microbial community in oak and pine forests. • Soil fauna show higher preference for Na-added litters. • Regardless of direction, Na amendment significantly decreased the strength of HFA. Sodium (Na) can affect ecosystem function by altering soil fauna and microbial community composition and abundance. Sodium's potential influences on plant-soil interactions, such as home-field advantage (HFA: enhanced decomposition in a home environment compared to an away environment), in relation to litter decomposition remains unclear. To fill this knowledge gap, we conducted a ten-month reciprocal litter transplant field experiment with Na amendments (0.005% and 0.5% water solution of NaCl) in both a subtropical broad-leaved forest dominated by Quercus variabilis (oak) and a coniferous artificial forest planted by Pinus massoniana (pine) in China. Litterbags with different mesh sizes were used to partition the impact of soil biota groups on the HFA. The results showed that 0.005% Na amendment facilitated litter decomposition as well as carbon (C) and nitrogen (N) mineralization by enhancing soil extracellular enzyme activity and soil faunal abundance. But 0.5% Na amendment inhibited litter decomposition in fine-mesh litterbags by decreasing microbial activity, and promoted litter decomposition in coarse-mesh litterbags by attracting more soil fauna. In the control plots, we observed a negative HFA in coarse-mesh litterbags (with most soil fauna and all soil microorganisms), and a positive HFA in fine-mesh litterbags (with complete exclusion of meso-and macrofauna). Whether the HFA was positive or negative (i.e. regardless of the direction of the HFA), Na amendments significantly decreased the magnitude of HFA by increasing the similarity of microbial community composition between the incubation fields ('home' vs. 'away') and decreasing selective foraging of soil fauna for different leaf litters. In sum, our results indicate that anthropogenic Na enrichment can decrease the effects of HFA through the modification of soil microbial and faunal communities, and thereby affect C sequestration and N cycling in subtropical forests. [ABSTRACT FROM AUTHOR]

The river–lake transition zone is affected by many environmental factors, leading to significant dynamics and complexity. This makes the boundary unclear, and not enough attention has been paid to this problem by scholars, even though it has great significance for research on water quantity, water quality, and the aquatic environment. In this paper, we define this transition zone, define its upper and lower boundaries, and develop the method for defining the hydrologic boundary. It includes a method for defining the upper boundary, based on the flow velocity mutation point, and a method for defining the lower boundary, based on the velocity gradient field. We then used this approach to examine the transition zones between the Fu River, Baigou Canal, and Baiyangdian Lake in China as a case study. We found that the upper boundary of the Fu River–Baiyangdian Lake transition zone was 2.35 km upstream of the lake's inlet; the lower boundary was farthest from the lake's inlet in July, and the maximum area of the transition zone was 2.603 km2. The lower boundary was closest to the lake's inlet in March, when the minimum area was 1.598 km2. The upper boundary of the Baigou Canal–Baiyangdian Lake transition zone was 2.18 km upstream from the lake inlet, and the lower boundary was farthest from the lake's inlet in August, when the maximum area was 2.762 km2. The lower boundary was closest to the lake's inlet in April, when the minimum area was 0.901 km2. [ABSTRACT FROM AUTHOR]

Although numerous studies have demonstrated the toxic effects of fine particulates less than 2.5 µm (PM2.5) on the health of humans, little information is available on the ecotoxicity of PM2.5. Water-soluble inorganic ions (WSII, including Na+, NH4+, K+, Mg2+, Ca2+, Cl−, NO3−, and SO42−) can compose more than 60% of PM2.5. To better understand the possible impacts of WSII-PM2.5 on leaf litter decomposition, we conducted an experiment in which two leaf litters from oak (Quercus variabilis) and pine (Pinus massoniana) dominant forests in subtropical China were incubated in microcosms containing their respective forest soils and treated with WSII-PM2.5. Our results showed that, after six-months of decomposition, the WSII-PM2.5 treatments inhibited leaf litter decomposition rates, carbon and nitrogen loss, microbial biomass, and enzyme activities in the two forests. In addition, higher WSII-PM2.5 concentration led to stronger negative effects. Comparative analysis showed that the negative effects of WSII-PM2.5 on oak forest were greater than on pine forest, relating to the higher susceptibility to changes of soil microenvironment in oak forests. WSII-PM2.5 may influence decomposition through soil acidification and salinization, which could also cause a sub-lethal depression in soil isopod activity. However, in the first month of decomposition, mass loss of the oak and pine leaf litters under the low concentration WSII-PM2.5 were 21.63% and 35.64% higher than that under the control, respectively. This suggests that transitory low concentrations of WSII-PM2.5 have a promoting effect on decomposition. Long-term PM2.5 exposure, therefore, may have profound ecosystem consequences by altering the balance of ecosystem carbon flux, nutrient cycling, and humus formation in the future. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are universal organic pollutants in the agro ecosystems in China, therefore, it is important to understand the uptake and accumulation of PAHs in crops growing on PAHs contaminated soils for human health risk assessments. Water management is a common practice to maintain high grain yields during wheat production. However, the effects of soil water content on the accumulation and translocation of PAHs in wheat are still not clear. The main objectives of the present study were to investigate the effects of soil water content on the accumulation of three selected PAHs (Σ 3 PAHs, phenanthrene, anthracene and pyrene) in wheat during whole plant growth stage and on translocation or remobilization of Σ 3 PAHs from vegetative tissues to wheat grains. Winter wheat (Triticum aestivum cv. Xiaoyan22) were grown on Σ 3 PAHs spiked soils maintaining 80%, 60% or 40% water-holding capacity during the whole plant growth stage. Plant samplings were performed at jointing, anthesis or maturity stage, respectively. The present study showed that grain yield and biomass of the crop increased with soil water content increasing. Transpiration rate of wheat leaf under 80% and 60% water-holding capacity treatments was significantly (p < 0.05) higher than that under 40% water-holding capacity treatment at both anthesis and filling stage. Soil water content and plant growth stage had significant (p < 0.0001) effects on concentrations of phenanthrene, anthracene and pyrene in winter wheat. When exposed to 0, 15, 60, and 150 mg kg−1 Σ 3 PAHs in soils, Σ 3 PAHs concentrations in the grains under 60% water-holding capacity treatment were 46.6%, 69.9%, 89.5% and 81.7% of those under 80% water-holding capacity treatment, respectively. The highest concentrations of Σ 3 PAHs in the crop were recorded at anthesis stage. The distribution of PAHs in different tissues of wheat varied among different soil water treatments and plant growth stages. The present study indicated that optimizing soil water content during winter wheat production could apparently reduce concentrations of Σ 3 PAHs in grains via influence root uptake of Σ 3 PAHs and translocation of Σ 3 PAHs from stem or leaf into grain, suggesting the potential of water management to cope with PAHs contamination in crops growing on PAHs contaminated soils. Image 1 • Concentrations of Σ 3 PAHs in wheat were consistently enhanced with the increase of corresponding concentrations in soils. • Pattern of accumulation of Σ 3 PAHs in the whole plant varied among soil water content treatments. • Optimizing water management during wheat production could reduce PAHs accumulation in wheat grain. [ABSTRACT FROM AUTHOR]

Creating a soil habitat is the first step to manage soil health for long‐term soil quality and output. This means using soil management methods that lessen the soil uproar. An experiment was established in 2016 and 2017 on a middle term (7 years) consistent tillage method in typical Latosolic red soil of Southern China to access the effects of four treatments: subsoiling (SS), two passes of rotary tillage (2RT), two passes of rotary tillage + subsoiling (2RTSS), and zero tillage (ZT), on soil organic carbon, soil total nitrogen, soil biological activities (bacteria, fungi, actinomycetes, urease, catalase, and phosphatase), and maize grain yield. The results showed that mean SOC, total N, biological activities, and maize grain yields were affected significantly (p < 0.05) by tillage methods. Compared with SS, 2RT, and 2RTSS, ZT had higher SOC, total N, soil bacteria, and soil actinomycetes in the 0–40 cm soil depth. The highest levels of fungi, urease, catalase, and phosphatase were recorded under SS in the 0–40 cm soil depth. Average maize grain yield of 7.37 ton/ha (9.81%) was recorded under SS compared to under ZT. Overall, we conclude that SS could be adopted as a promising soil management method for soil health, quality, and productivity resulting in a sustainable agricultural system. [ABSTRACT FROM AUTHOR]

A two-year field experiment was conducted to assess the influence of subsoiling (SS), two passes of rotary tillage (2RT), two passes of rotary tillage + subsoiling (2RTSS), and zero tillage (ZT) on soil physical properties and maize grain yield in Latosolic red soil of Southern China in a randomized complete block design with three repeats. Results showed that, SS recorded lowest soil bulk density (1.41 g cm-3 ), soil penetration resistance (1.81 MPa), soil gravimetric water content (21.12%), and volumetric water content (29.19%), resulting in highest soil porosity (47.36%) at 0-40 cm soil depth. Highest plant, ear height, ear length, ear weight, number of rows per ear, and number of grains per row were observed under SS. Also, maximum grain yield 7.37 ton ha-1 (9.81%), dry matter, harvest index, and 1000-grain weight were recorded under SS. Overall, SS improved soil physical properties and facilitated highest maize yield and yield components, and therefore, SS could be adopted as a strategy for higher productivity leading to a sustainable agricultural system under the changing climatic conditions. [ABSTRACT FROM AUTHOR]

• The present study reported the prevalence of Fasciola spp. in snails from large-scale regions of China. • In China, climate and topography could affect the Fasciola spp. infection in snails. • A highly positive correlation between snails and animal infection was found in central and eastern China. • Infected snails could be an indispensable risk factor for fasciolosis transmission. Fasciolosis is a zoonotic disease as 600 million animals have been infected, and 180 million people are at risk of the infection in the world. Snail as the intermediate host of Fasciola is an essential and important factor in the transmission of fasciolosis, while its potential risk for transmission has not been studied. In this study, 3561 snails collected from large-scale regions of China were examined by nest-PCR method. A total of 345 snails were positive for Fasciola spp. , with an overall prevalence of 9.7%. Prevalence in central and southern China, characterized by a subtropical monsoon climate, was relatively low (8.0%), while a high infection rate (36.9%) was found on the plateau area (altitude > 500 m). In combination with previous findings, the study showed a highly positive correlation between snails and animal infection in central and eastern China, thus indicating that infected snails could be an indispensable risk factor for fasciolosis transmission. Epidemiological surveillance of snails will help assess the risk of fasciolosis in humans or ruminants, which promotes future prevention of this zoonotic disease. [ABSTRACT FROM AUTHOR]

Aboveground consumers can shape belowground processes in brown-food webs of forests by converting litter into faeces. Woodlice are one of the important aboveground consumer groups driving the dynamics of belowground soil. Although considerable data on litter decomposition exists, the indirect effects of woodlice (different qualities of faeces) on litter decomposition need to be explored further. In this study, we assessed the influence of isopods ( Armadillidium vulgare ) and its by-products (three contrasting qualities of faeces) on the decomposition of broad-leaf and needle litter via soil incubation. Litter mass loss, soil microbial biomass and soil extracellular enzyme activities treated with different isopod by-products were determined in six-month laboratory incubations. The results showed that after incubation, the indirect effect of fauna (faeces) did not significantly increase broad-leaf litter decomposition. However, faeces of isopods fed on high-quality legume litter significantly increased needle litter decomposition. The effects of isopod faeces on microbial activities were significant: most of the soil microbial biomass and extracellular enzyme activities increased significantly compared with non-faeces treatments in the soil of broad-leaved and coniferous forests; and high-quality faeces strengthened the correlation of litter mass loss with peroxidase and phenol oxidase in coniferous forest. The result suggests that faeces with higher concentrations of nitrogen and labile carbon can mediate the decomposition of refractory materials like lignin and phenolic compounds, which might be highly relevant for the litter decomposition process in ecosystems with high macrofauna abundance. This study infers that the indirect effect of isopods (faeces) on litter decomposition depends on the quality of the litter they consumed and the type of decomposing litter. Isopods indirectly accelerate the nutrient-poor litter decomposition process by converting high-quality litter into faeces. As such, the negative effects of litter recalcitrance on microbial decomposition in mixed forests are indirectly alleviated. [ABSTRACT FROM AUTHOR]

The quality of water in urban parks is closely related to people's daily lives, but the pollution caused by microplastics in park water and sediments has not been comprehensively studied. Therefore, eight typical parks in the urban area of Changsha, China, were selected, and Raman spectroscopy was used to explore the spatial distributions and compositions of the microplastics in the water and sediments, analyze their influencing factors, and evaluate their environmental risks. The results showed that the abundances of surface water microplastics in all parks ranged from 150 to 525 n L -1 , and the abundances of sediment microplastics ranged from 120 to 585 n kg -1 . The microplastics in the surface water included polyethylene terephthalate (PET), chlorinated polyethylene (CPE), and fluororubber (FLU), while those in the sediments included polyvinyl chloride (PVC), wp-acrylate copolymer (ACR), and CPE. Regression analyses revealed significant positive correlations between human activities and the abundances of microplastics in the parks. Among them, the correlations of population, industrial discharge and domestic wastewater discharge with the abundance of microplastics in park water were the strongest. However, the correlations of car flow and tourists with the abundance of microplastics in park water were the weakest. Based on the potential ecological risk indices (PERI) classification assessment method, the levels of microplastics in the waters and sediments of the eight parks were all within the II-level risk zone (53-8,549), among which the risk indices for Meixi Lake and Yudai Lake were within the IV risk zone (1,365-8,549), which may have been caused by the high population density near the park. This study provides new insights into the characteristics of microplastics in urban park water and sediment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Yao, Li, Qi, Wan, Tang, Han, Tian and Liu.)

As an important food production area in the north of China, the Hetao plain is extremely vulnerable to nitrate pollution caused by agricultural production activities and additional factors. Thus, it is of great significance for the environmental protection and rational use of groundwater to detect the current situation of groundwater nitrate pollution, temporal and spatial evolution characteristics, and main influencing factors in the Hetao irrigation district. We selected the Wualte irrigation area as the study area, and the characteristics of temporal and spatial changes in groundwater nitrate concentration and the main influencing factors in this area were explored. We used statistical analysis to analyze the nitrogen content of groundwater in the study area, and the Piper three-line diagram was used to explore the characteristics of chemical composition and evolution; furthermore, we used ion ratio and correlation analysis methods to explore the source of NO 3 - -N in groundwater. The results showed that NO 3 - -N was the main existing form of nitrogen in the Wulate irrigation area, and its concentration varied from 0.01 to 60.00 mg·L -1 , with an exceeding standard rate of 10.50%. In terms of time, the characteristic of time change was that the NO 3 - -N concentration in August of groundwater was the highest (average 6.61 mg·L -1 ), followed by that in October (6.22 mg·L -1 ) and November (6.25 mg·L -1 ), and that in March (average value of 1.77 mg·L -1 ) was the lowest. With the influence of rainfall and irrigation, the NO 3 - -N in the soil was infiltrated into the groundwater, showing the characteristic that wet season and concentrated irrigation periods were higher than those in other periods. Spatially, it appeared as southwest (8.87 mg·L -1 )>northwest (4.25 mg·L -1 )>east (0.89 mg·L -1 ), mainly due to the original geological conditions, land use, and domestic waste stacking. In addition, the concentration of NO 3 - -N of groundwater in the study area was closely related to the depth of groundwater and redox conditions but was relatively less affected by the concentration of water chemical ions. Therefore, identifying the temporal and spatial distribution characteristics and main sources of groundwater nitrogen pollution can provide a scientific basis for scientific fertilization, groundwater nitrate pollution control, and water safety.

The National Certification Commission for Acupuncture and Oriental Medicine (NCCAOM) is the only national institution for the accreditation of clinical practice of acupuncture and Oriental (Chinese) Medicine in the United States. Its qualification certificate or examination certificate is a mandatory document for 47 states and Washington, D.C. to issue the practice license. According to the latest information of the NCCAOM official website, this paper introduced the preceptor qualifications of the apprenticeship, studying hours, quality control, and the evaluation at the end of apprenticeship. The paper also discussed the enlightening and referential effects of the American system to apprenticeship policy in China.

In order to investigate level and potential sources of polycyclic aromatic hydrocarbons (PAHs) in wheat fields affected by coal combustion in Henan and Shaanxi Provinces and to investigate distribution and transfer of PAHs in winter wheat grown in the areas, various tissues of the crop and the corresponding rhizosphere soils were collected during the harvest season of winter wheat. The mean concentrations of USEPA 15 priority PAHs (sum of the three- to six-ring PAHs) ranged from 486 to 1117 μg kg -1 in the rhizosphere soils, indicating serious PAH contamination. Based on both the isomeric ratios of PAHs and a principal component analysis (PCA), the main sources of PAHs in the agricultural soils were from combustion of biomass, coal and petroleum, and petroleum. ∑ 15 PAHs were significantly (p < 0.001) higher in the roots (287-432 μg kg -1 ) than those in aerial tissues (221-310 μg kg -1 ). There were two decreasing gradients of PAH concentrations, one from roots, stems to leaves, and the other from glumes to grains. Regardless of sampling sites, most PAHs detected in the roots and in the aerial tissues were three-ring PAHs (acenaphthene, acenaphthylene, fluorene, phenanthrene, and anthracene) and the percentages of three-ring PAHs were much higher in the aerial tissues (72.5-82.7%) than in the roots (49.5-74.0%) and in the rhizosphere soils (36.3-65.7%). The distribution of PAHs with different ring numbers in the stems, leaves, and glumes was quite similar to each other but was significantly different from that of the roots and rhizosphere soils. Combined with significant results from partial correlation and linear regression models, the present study suggested that partial three- to four-ring PAHs in the aerial tissues are derived from root-soil uptake and that six-ring PAHs may come from the air-to-leaf pathway, although the quantity contribution of foliar uptake and root uptake was yet to be further studied.