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1

Influence of the Three Gorges Reservoir on the vegetation of its drawdown area: effects of water submersion and temperature on seed germination of Xanthium sibiricum (Compositae)

100%
Wang Q., Yuan X., Liu H.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 1
Xanthium sibiricum, an annual weed, unexpectedly and dramatically occupied the exposed drawdown area after water had been impounded for the first time in the newly created Three Gorges Reservoir in China. In order to explain this phenomenon and establish an appropriate management strategy, the effects of constant submersion on seed viability and germination of X. sibiricum were investigated at two constant temperature regimes (25oC and 30oC) under artificial laboratory conditions. The results indicated that the seeds of X. sibiricum exhibited a high level of tolerance of submersion and up to 99% of seeds were viable in each treatment regime. The effect of submersion on germination was not obvious at 25oC until the submersion was prolonged for 180 days, while at 30oC the eventual germination rate of X. sibiricum, even after submergence for only one day, was significantly improved. The speed of germination was also consistently accelerated by prolonged periods of submersion. The proportion of seeds that germinated in all treatments combined was less that 56% due to seed dimorphism, thereby providing a seed bank. We conclude that the interaction between long-term winter flooding and high temperature in summer is the major reason that X. sibiricum was able to occupy the newly exposed drawdown area in the absence of competition. These findings provided further insight into how germination strategy and reservoir water-management regime contributed to this dramatic species outbreak.
2

Fractionation and bioavailability of trace elements in wuyi rock tea garden soil

100%
Ye H., Li G., Yuan X., Zheng M.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 1
The chemical fraction of elements has been widely employed in the study of soil chemistry, plant nutrition, and environmental science. For this study we conducted a comprehensive survey on trace elements (Hg, As, Cd, Cr, Pb, Cu, Zn, Mn, Se, Mo, Co, etc.) from the rock tea gardens in Wuyishan, southeastern China. Our results demonstrate that: 1) The contents of heavy metals such as Hg, Pb, As, and Cd in the soil meet the environmental requirements for the growing area of tea (NY/T 853-2004), and the soil in the studied area contains sufficient Mn, Mo, and Se for tea plant growth, with a slight lack of Co. 2) The exchangeable fraction is determined to be the dominant fraction of Cd, which originates from an anthropogenic source and possesses high bioavailability from elemental speciation analysis. 3) The heavy metal contents in all the tea leaf samples are within the safe range, and the average values of the element enrichment coefficients of the tea leaves decrease in the order: Mn > Cu > Hg > Zn > Se > Cd > Mo > Co > As > Pb > Cr.
3

L1-ORF1p and Ago2 are involved in a siRNA-mediated regulation for promoter activity of L1-5’UTR

88%
Shi L., Shi H., Lou L., Yuan X., Zhu Y.
Folia Histochemica et Cytobiologica
|
2019
|
tom 57
|
nr 2
4

Potholes of mountain river as biodiversity spots: structure and dynamics of the benthic invertebrate community

88%
Ren H., Yuan X., Yue J., Wang X., Liu H.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 1
Temporary freshwater rock pools, as special, small-sized and isolated habitats, provide ideal systems for studying island biogeography and ecological theories and processes. In this study, a total of 70 potholes of mountain rivers were sampled during the four seasons from November 2013 to October 2014 to assess the structure of the benthic invertebrate community and to identify the relationships between habitat characteristics and the community composition. Pothole area ranged from approximately 0.01 to 0.39 m², and pothole depth ranged from 0.03 to 0.74 m. Forty-three taxa belonging to 37 families and 16 orders were collected from the potholes. The highest numbers of benthic invertebrate taxa were observed in summer and the highest average number of taxa per pothole (8.5) was observed in autumn. The diversity was the highest in spring, and the average densities of benthic invertebrates were highest in autumn. Large potholes supported more taxa than small ones and significant relationships between richness and pothole area, richness and water volume were observed. The results of Redundancy Analysis show that the community composition of benthic invertebrates in the potholes was closely correlated with water temperature, pothole area and water depth. Our results indicate that benthic invertebrate communities in river potholes are mainly structured by water depth, pothole area and water volume. The seasonal changes are also an important factor determining the presence/absence of certain taxa.
5

Seasonal distribution of suspended particulate matter off China’s subei coast

88%
Song Z., Li J., Meng F., Tang W., Yuan X.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 2
In this study, the spatial distribution and seasonal changes of suspended particulate matter (SPM) concentrations near radial sand ridge areas off China’s Subei Coast are addressed, based upon field measurements conducted during spring and autumn. The results show that the SPM concentrations have higher values in spring than in autumn, and that higher concentrations of SPM occur in the near-bottom layer in both seasons; also, the nearshore areas have higher concentrations of SPM than offshore. In addition, a robust linear relationship was established between the SPM concentrations (mgL⁻¹) and in situ remote sensing reflectance (Rrs) (R² = 0.944, n = 39), and then the concentrations of SPM are retrieved from the satellite images, which have a good corresponding relationship with in situ SPM concentrations. There are significant differences between SPM concentrations in spring and those in autumn. The SPM in the study area is mainly derived from the resuspension of the seabed sediments in the radial sand ridges (abandoned Huanghe-Changjiang River multiple delta).
6

Negative soil respiration fluxes in unneglectable arid regions

88%
Wang W., Chen X., Pu Z., Yuan X., Ma J.
Polish Journal of Environmental Studies
|
2015
|
tom 24
|
nr 2
This study examines the hypothesis that soil respiration fluxes are always positive, neglecting negative fluxes in arid regions that characterize more than 30% of Earth’s total land area. To cut down uncertainty, we focus on non-vegetated areas at a typical, large arid region (Central Asia). Soil respiration fluxes were reconciled as a direct sum of influxes (CO₂ fluxes entering soils) and effluxes (CO₂ fluxes released from soils). It was indicated that the annual average of effluxes was only 8% higher than that of influxes in 1979-2011. At typically alkaline sites (soil pH>9.5), extreme local annual average of soil respiration fluxes are negative. Therefore, negative soil respiration fluxes in arid regions are unneglectable. Although the soil respiration flux is useful as a measure of CO₂ effluxes from the soils and CO₂ influxes to the soils, its value as a measure of ecosystem processes is very much limited.
7

Effects of salt stress and exogenous Ca2plus on Na plus compartmentalization, ion pump activities of tonoplast and plasma membrane in Nitraria tangutorum Bobr. leaves

88%
Liu W., Yuan X., Zhang Y., Xuan Y., Yan Y.
Acta Physiologiae Plantarum
|
2014
|
tom 36
|
nr 08
Nitraria tangutorum Bobr. is a typical halophyte with superior tolerance to salinity. However, little is known about its physiological adaptation mechanisms to the salt environment. In the present study, N. tangutorum seedlings were treated with different concentrations of NaCl (100, 200, 300 and 400 mmol L⁻¹) combined with five levels of Ca²⁺ (0, 5, 10, 15 and 20 mmol L⁻¹) to investigate the effects of salt stress and exogenous Ca²⁺ on Na⁺ compartmentalization and ion pump activities of tonoplast and plasma membrane (PM) in leaves. Na⁺ and Ca²⁺ treatments increased the fresh weight and dry weight of N. tangutorum seedlings. The absorption of Na⁺ in roots, stems and leaves was substantially increased with the increases of NaCl concentration, and Na⁺ was mainly accumulated in leaves. Exogenous Ca²⁺ reduced Na⁺ accumulation in roots but promoted Na⁺ accumulation in leaves. The absorption and transportation of Ca²⁺ in N. tangutorum seedlings were inhibited under NaCl treatments. Exogenous Ca²⁺ promoted Ca²⁺ accumulation in the plant. Na⁺ contents in apoplast and symplast of leaves were also significantly increased, and symplast was the main part of Na⁺ intracellular compartmentalization. The tonoplast H⁺-ATPase and H⁺-PPase activities were significantly promoted under salt stress (NaCl concentrations ≤ 300 mmol L⁻¹). PM H⁺-ATPase activities gradually increased under salt stress (NaCl concentrations ≤ 200 mmol L⁻¹) followed by decreases with NaCl concentration increasing. The tonoplast H⁺-ATPase, H⁺- PPase and PM H⁺-ATPase activities increased first with the increasing exogenous Ca²⁺ concentration, reached the maximums at 15 mmol L⁻¹ Ca²⁺, and then decreased. The tonoplast and PM Ca²⁺-ATPase activities showed increasing trends with the increases of NaCl and Ca²⁺ concentration. These results suggested that certain concentrations of exogenous Ca²⁺ effectively enhanced ion pump activities of tonoplast and PM as well as promoted the intracellular Na⁺ compartmentalization to improve the salt tolerance of N. tangutorum.
8

Origin and risk assessment of potentially harmful elements in river sediments of urban, suburban, and rural areas

88%
Yuan X., Li T., Li J., Ye H., Ge M.
Polish Journal of Environmental Studies
|
2013
|
tom 22
|
nr 2
The Changjiang Delta Region is a rapidly urbanizing area in China. But this area still reveals different anthropogenic activities and urbanization levels. River sediments from urban, suburban, and rural areas were studied to characterize potentially harmful elements (PHEs) and their ecological risks. Chemical compositions of sediments were analyzed, which revealed pronounced differences in three areas. Al₂O₃, Fe₂O₃, CaO, and MgO were elevated in the urban sediments. Sediments from the rural area showed high organic matter. CaO and TOC of sediments fluctuated significantly in the suburban area. They are associated with the local geological provenance and sediment circumstance. The enrichments of PHEs in sediments of urban rivers were prevalent, among which Cd and As were prominent. Concentrations of PHEs in the suburban area fluctuated significantly. Lead and Cu were obviously enriched in this area. Rural sediments had relatively low concentrations of PHEs, which were also stable in the regional distribution, although As showed a slight enrichment. Based on RI values from Hakanson, the urban sediments showed moderate to considerable ecological risk. And the suburban sediments were in moderate ecological risk, except some high-risk samples. The majority of rural sediments revealed low ecological risk. Of these hazardous elements, Cd, Hg, and Pb contribute the largest proportion of the total ecological risk. It is evident that the urbanization level influences the distributions and contamination grades of PHEs for river sediments of the Changjiang Delta Region.
9

Edge effects on tree growth and species diversity in forests of different types and ages

88%
Li J., Zhao C., Peng Y., Hu Y., Yuan X.
Polish Journal of Ecology
|
2018
|
tom 66
|
nr 3
Edge to interior gradients in forest ecosystems can influence the species composition and community structure as a result of variations in micro-environment. In this study, the edge effects on stand productivity and plant species diversity were investigated in two adjacent types of forests in central-southern China: Chinese fir adjacent with pine forests and Chinese fir adjacent with broad-leaved forests. A total of 48 sample plots for overstory and 240 sample quadrates for understory in different stand ages were set up. The tree growth parameters were measured in the overstory while the plant species diversity was measured in both overstory and understory of the examined forests. The results showed that DBH (tree diameter at the breast height), tree height and stand volume in overstory increased from the central areas (CA) of forests to the edge areas (EA), and the plant species richness and diversity in understory were greater in EA than in CA. The edge effect was greater in Chinese fir paired with broad-leaved forests than in Chinese fir paired with pine forests. The edge effect decreased in an order as young aged stands > middle aged stands > mature aged stands in the studied forests. The changes in tree growth and species diversity in the edge area compared to the interior were mainly attributed to the alteration of micro-environmental factors such as light density, temperature and moisture. Our results suggest increasing forest productivity and plant species diversity could be achieved by making more edges in the forests.
10

Influence of heavy metals and nutrient concentrations on selenium geochemical behavior in soil-rice system

76%
Li T., Yuan X., Song Y., Chen H., Liu Q., Hu S.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 1
Selenium deficiency in crops has become a subject of growing concern where soil Se concentration is low. The mechanisms of Se translocation in the soil-rice system is very complex and the influence of heavy metal elements and nutrient concentrations on Se translocation in the soil-rice system is unknown. Our study investigated concentrations of Se, heavy metals like Hg, Cd, and Pb, and nutrient elements like Ca, K, P, and S in soils and rice tissues (roots, stems, and grains) in different industrial regions in Jiangsu Province, China. The transfer of Se in the soil-rice system was calculated by transfer coefficients (TC Se) in this study. The results showed that Se transfer from soil to roots and from stems to grain were key steps for controlled Se concentration in rice grains. The multiple linear regression analysis makes an implication that some elements influence the Se transfer significantly: soil K and Hg may suppress Se entering rice roots; B, Cu, and Mo in rice root may restrain Se transfer from root to stem; and S, Cr, P, and Mg in rice stem had negative effects on Se accumulation in rice grain. Therefore, reducing heavy metal pollution and managing fertilizer amounts may elevate Se concentration in rice grain, especially when Se concentration in soils is low.
11

Elman-based forecaster integrated by Adaboost algorithm in 15 min and 24 h ahead power output prediction using PM 2.5 values, PV module temperature, hours of sunshine, and meteorological data

76%
Zhou J., Li W., Yu X., Xu X., Yuan X., Wang J.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 3
Nowadays, with the depletion of fossil energy and deterioration of environmental quality, solar energy is perceived to be a renewable and clean energy. While developing rapidly all over the world, solar energy is also faced with many challenges resulting from its inherent properties. In order to reduce the impact on the grid and facilitate scheduling, it is a growing problem to build a feasible model to forecast PV power with high precision. Therefore, this paper proposes an Elman-based forecaster integrated by Adaboost algorithm, namely Adaboost + Elman. Before forecasting, input variables containing PM 2.5 values, temperature of the PV module, sunshine hours, and meteorological data are made using correlation, clustering, and discriminate analysis to avoid information redundancy and improve the generalization ability of the model. To verify the developed model’s application to short-term PV forecasting in two different time scales, data of Huangsi in 2016 are used for model construction and verification. An additional 7 models are introduced to make comparison. Experimental results prove that the proposed model is effective and practicable for two different scales of short-term PV power prediction.
12

Effect of long-term winter flooding on the vascular flora in the drawdown area of the Three Gorges Reservoir, China

76%
Wang Q., Yuan X., Liu H., Zhang Y., Cheng Z., Li B.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 1
The dam construction and water impoundment have extensively altered flow regime and riparian ecosystems. However, the effect of long-term winter flooding of reservoir on plants of drawdown area is poorly known. The Three Gorges Dam in China, the largest dam in the world, created a drawdown area of 348.93 km2 between 145 m and 175 m above sea level around its reservoir. The drawdown area was submerged for more than half year in winter and exposed in summer. In the summer of 2009, the vegetation of fourteen sites in the drawdown area was investigated to determine the impact of winter flooding on vascular flora and to explore flood-tolerant species for vegetation reconstruction. One hundred and seventy five species of 58 families were recorded in present work，which indicated that 55% of vascular flora species disappear or became rare. The number of perennial species decreased to 50%. Therophytes, with 87 taxa, were the dominant life form. Strictly aquatic species were rather scarce for summer drought. Mean vegetation cover in the drawdown area was more than 70%. Species richness and vegetation cover along the elevation gradient exhibited a negative pattern correlated with flooding duration. The remarkable reduction of plant richness, variation of life form composition and alternation of dominant species indicated the strong influence of long-term winter flooding on vascular flora. Cynodon dactylon and Cyperus rotundus was highly resistant to long-term winter flooding and summer drought. Eight hardwoods (Vitex negundo, Morus alba, Sapium sebiferum, Glochidion puberum, Rhus chinensis, Melia azedarach, Pterocarya stenoptera and Trema levigata) exhibited high tolerance to winter flooding and may be potential candidates for vegetation restoration.
13

De novo transcriptome sequencing of pakchoi (Brassica rapa L. chinensis) reveals the key genes related to the response of heat stress

76%
Xu H., Chen L., Song B., Fan X., Yuan X., Chen J.
Acta Physiologiae Plantarum
|
2016
|
tom 38
|
nr 10
14

Quantitative evaluation of soil erosion in the upper Minjiang River Basin of China based on integration of geospatial technologies using RUSLE

76%
Ye H., Hua W., Huang C., Huang T., Wang H., Yuan X., Yang H.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 5
15

Simulated study on the degradation of monoand bi-component dye wastewater by TiO2/H3PW12O40 film excited under solar-like radiation

76%
Lu N., Wang Y. Q., Luo M., Qu J., Guan J. N., Yuan X.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 3
The objective of this work was to develop an effective technique for removing multiple component dye wastewater. Saturation Keggin-type phosphotungstic acid (H₃PW₁₂O₄₀) was introduced to prepare TiO₂/H₃PW₁₂O₄₀ film for photocatalytic degradation of four monocomponent dye wastewater as rhodamine B (RhB), methyl orange (MO), malachite green (MG), and alizarin red (ARS), as well as bicomponent dye wastewater of RhB-MG with different volume ratio. The results indicated that the photocatalytic efficiency of TiO₂/H₃PW₁₂O₄₀ film toward cation dyes (98.5% RhB and 95.2% MG) was higher than that of anion dyes (89.8% ARS and 48.8% MO) after 240 min solar-like irradiation, during which the adsorption acted as the controlling process, whereas in the bicomponent dye solution of RhB-MG, the degradation RhB was restrained due to the competition for the active sites of catalyst surface with MG. This work could provide necessary information for the treatment of multiple component dye wastewater in practical applications.
16

Using near infrared spectroscopy to quickly analyze different nitrogens during the shortcut biological removal of nitrogen from a polluted river

64%
Huang J., Li M., Zhang H., Zhang Y., Liu J., Sun W., Ma T., Xu Y., Yuan X.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 4
During shortcut biological nitrogen removal in a polluted river, total nitrogen, ammonia nitrogen and nitrite nitrogen were quantified by near infrared spectroscopy and the synergy interval partial least squares (siPLS) algorithm. Spectral data of 138 water samples were obtained with a near infrared spectrometer. In addition, the real values of total nitrogen, ammonia nitrogen and nitrite nitrogen were measured with traditional chemical methods. SiPLS analysis models of total nitrogen, ammonia nitrogen and nitrite nitrogen were built through the siPLS algorithm based on spectral data and realvalues. The results obtained from the siPLS analysis model of total nitrogen revealed that, when the full spectra were divided into 19 intervals, the combination of the 7th, 12th and 19th subintervals yielded the best model. The correction coefficient (Rp) is 0.9931, with the root mean squared error of calibration (RMSECV) being 1.7869. The results obtained from the siPLS analysis model of ammonia nitrogen indicated that, when the full spectra were divided into 16 intervals, the combination of the 1st, 7th, 15th and 16th subintervals yielded the best model. The Rp is 0.9947 and the RMSECV is 1.3419. For nitrite nitrogen, the siPLS analysis model indicated that, when the full spectra were divided into 16 intervals, the combination of the 7th and the 11th subintervals yielded the best model. The Rp and RMSECV was 0.9951 and 1.0518. These findings demonstrated that the proposed approach may effectively analyze the concentrations of total nitrogen, ammonia nitrogen and nitrite nitrogen during the treatment of a polluted river based on shortcut biological nitrogen removal. This approach,which is based on near infrared spectroscopy, is fast and accurate for the detection of different types of nitrogen in water.
17

A computationally constructed ceRNA interaction network based on a comparison of the SHEE and SHEEC cell lines

64%
Sun J., Yan J., Yuan X., Yang R., Dan T., Wang X., Kong G., Gao S.
Cellular and Molecular Biology Letters
|
2016
|
tom 21
18

The effect of habitat on methane emission from an alpine wetland

64%
Chen H., Wu N., Gao Y., Yao S., Wang Y., Tian J., Sun G., Yuan X.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 2
377-381
Alpine wetland is a source for methane (CH₄), an important greenhouse gas, but little is known about how this habitat influences the emission. To understand this wetland habitats were selected at the altitude of 3430 m a.s.l. (in National Wetland Nature Reserve of Zoige, Quingle – Tibetan Plateau) and the methane flux was measured with static chambers in three different sites, including hollows with Carex muliensis Hand – Mazz. and Eleocharis valleculosa Ohwi f. setosa (Ohwi) Kitagawa., grass hummocks composed of Kobresia tibetica Maxim, Cremanthodium pleurocaule R. D. Good, Potentilla bifurca L. and Pedicularis sp. We have found that in alpine wetland these habitats significantly affect CH₄ emissions in the onset (April, 2006) and peak (August, 2005) stages of growing season.Hollows covered with Carex muliensis and Eleocharis valleculosa had higher values of emission than grass hummocks built by several grass species. Slight difference of CH₄ emission was found between two kinds of hollows with Carex muliensis and Eleocharis valleculosa. These results were consistent with the change of water table, which was found best correlated with CH₄ emissions (r²= 0.43, P <0.01) in the peak stage of growing season. Directly measured shoot biomass and plant heights were best related to CH₄ emissions (r²= 0.59, P <0.01). However, in the onset stage of growing season, variation of CH₄ emission may not be simply ascribed to changes in water table and vegetation structure.
19

Transcriptome-sequencing analyses reveal putative genes related to flower color variation in Chinese Rosa rugosa

64%
Sheng L., Xia W., Zang S., Zeng Y., Yuan X., Ning G., Zhang S., Feng L.
Acta Physiologiae Plantarum
|
2018
|
tom 40
|
nr 03
20

Genome-wide association study on chicken carcass traits using sequence data imputed from SNP array

64%
Huang S., He Y., Ye S., Wang J., Yuan X., Zhang H., Li J., Zhang X., Zhang Z.
Journal of Applied Genetics
|
2018
|
tom 59
|
nr 3
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