Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition

Hangzhou, China

Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition

Hangzhou, China
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Wang H.,Zhejiang University | Wang H.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Wang H.,U.S. Department of Agriculture | Wang H.,University of California at Riverside | And 12 more authors.
Chemosphere | Year: 2010

A laboratory study was conducted to investigate the mineralization of metsulfuron-methyl (MSM) in paddy soils in response to soil moisture, temperature and soil properties. The results indicated that MSM mineralization was relatively limited in the paddy soils when soil temperature was low. Only 2.2-6.0% of the applied 14C mineralized after 84 d of incubation at 15 °C. The mineralization of MSM was enhanced by increasing soil moisture and soil temperature. Soil moisture would have different impact on the response of MSM mineralization to variation in soil temperature. An increase of 10 °C accelerated the average rate of MSM mineralization by 2.3 times at 50% water-holding capacity (WHC) and 1.9 times at 40% WHC. Regression analysis showed that soil pH, organic carbon contents, microbial biomass carbon contents, and silt/clay fractions were the dominant factors affecting MSM mineralization, with pH as the most important factor. The relatively slow mineralization rate of MSM suggested long persistence of this herbicide in soil, thus increasing its potential ecological risk, especially when applied in alkaline soils and in cold areas. © 2009 Elsevier Ltd.


Wang H.,Ministry of Education Key Laboratory of Environment Remediation and Ecosystem Health | Niu Y.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Chai R.,Ministry of Education Key Laboratory of Environment Remediation and Ecosystem Health | Liu M.,Ministry of Education Key Laboratory of Environment Remediation and Ecosystem Health | Zhang Y.,Ministry of Education Key Laboratory of Environment Remediation and Ecosystem Health
Plant signaling & behavior | Year: 2013

This study demonstrates a potential signaling pathway of CO 2-dependent stimulation in lateral root (LR) formation. Elevated CO 2 increases production of nitric oxide (NO), which subsequently stimulates the generation of cytosolic Ca (2+) concentration by activating plasma membrane and/or intracellular Ca (2+)-permeable channels. Meanwhile, nitric oxide synthase (NOS), as one of the main NO source, requires Ca (2+) and CaM as cofactors. This complex interaction involves transduction cascades of multiple signals that lead to the LR formation and development. Finally, this review highlights the the role of Ca (2+) in the process that elevated CO 2 enhances the development of LRs through increased NO level.


Li J.,Zhejiang University | Li J.,Zhejiang Provincial Key Laboratory of Information Network Technology | Zeng L.,Zhejiang University | Zeng L.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition
Journal of Physics A: Mathematical and Theoretical | Year: 2010

We discuss in detail the effects of the multi-time-delayed feedback driven by an aperiodic signal on the output of a stochastic resonance (SR) system. The effective potential function and dynamical probability density function (PDF) are derived. To measure the performance of the SR system in the presence of a binary random signal, the bit error rate (BER) defined by the dynamical PDF is employed, as is commonly used in digital communications. We find that the delay time, strength of the feedback, and number of time-delayed terms can change the effective potential function and the effective amplitude of the signal, and then affect the BER of the SR system. The numerical simulations strongly support the theoretical results. The goal of this investigation is to explore the effects of the multi-time-delayed feedback on SR and give a guidance to nonlinear systems in the application of information processing. © 2010 IOP Publishing Ltd.


Liao M.,Zhejiang University | Liao M.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Xie X.,Zhejiang University | Ma A.,Zhejiang University | And 3 more authors.
Journal of Soils and Sediments | Year: 2010

Purpose: Cadmium (Cd) is a toxic heavy metal, accumulated in soil by anthropogenic activities and has serious effects on soil microbial activities in contaminated soils. Moreover, there is a lack of reliable data on the effects of Cd in the soil-plant system, since most of the information on Cd-microorganism interactions in soils are based on sewage sludge without plants. The main objective of this study was to assess the effects of Cd on soil microbial activities and community structure during growth of plant. Materials and methods: A greenhouse pot experiment was conducted to evaluate the impact of different concentrations of Cd on soil microbial activities during the growth of Chinese cabbage (Brassica chinensis) in two different soils. The field soils were used in this short-term (60 days) greenhouse pot experiment. The soils were spiked with different Cd concentrations, namely, 0, 1, 3, 8, 15, 30 mg Cd kg-1 oven dry soil, respectively. The experimental design was a 2 (soil) × 2 (vegetation/non-vegetation) × 5 (treatments (Cd)) × 3 (replicate factorial experiment). After 60 days, the study was terminated and soils were analyzed for selected microbial parameters, such as, microbial biomass carbon (Cmic), basal respiration and phospholipid fatty acids (PLFAs). Results and discussion: Application of Cd at lower concentrations (1 and 3 mg kg-1) resulted in a slight increase in Cmic, whereas Cd concentrations >8 mg kg-1 caused an immediate significant decline in Cmic, the ratio of Cmic to total organic C (Cmic/Corg) decreased and the metabolic quotient (qCO2, namely, the basal respiration CO2/Cmic) increased with elevated Cd concentration. However, the impact on soil Cmic and basal respiration caused by Cd was dependent from plant cover or soil properties. The results of PLFAs showed relative increase in fatty acid indicators for fungi and actinomycetes and gradual increase in the ratio of Gram-positive to Gram-negative bacteria which were responsible for these differences with increasing Cd concentration in the planted and unplanted soils. Conclusions: Soil microbial parameters, including, soil Cmic, the ratio of Cmic/Corg, qCO2, and community structure, may be sensitive indicators reflecting environmental stress in soil-Cd-plant system. However, further research work is needed for better understanding the changes in microbial community structure and actually impact on soil microbial community function. © 2010 Springer-Verlag.


Xie X.,Zhejiang University | Liao M.,Zhejiang University | Liao M.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Fang S.,Zhejiang University | And 6 more authors.
Journal of Hazardous Materials | Year: 2012

To investigate rhizosphere effects on the biodegradation of pyrene with the distance away from root surface in the rhizosphere of ryegrass (Lolium perenne L.), a glasshouse experiment was conducted using a multi-interlayer rhizobox where ryegrass were grown in a soil spiked with pyrene. The largest and most rapid dissipation of pyrene in planted soil appeared at 2mm zone from the root zone. The pyrene degradation gradient followed the order: near-rhizosphere>root compartment>far-rhizosphere soil zones. In contrast, there was no difference in pyrene concentration with distance in the unplanted soil. Dynamic changes of soil microbial biomass carbon (C mic) and the activities of both soil polyphenol oxidase and dehydrogenase were to some extent coincident with the degradation of pyrene with distance away from the root compartment in planted soils, which indicated the changes of soil microorganisms in different soil zones of rhizosphere were mainly responsible for the observed pyrene degradation. The largest C mic and activities of both soil polyphenol oxidase and dehydrogenase also occurred in near-rhizosphere, especially in 2mm zone from the root surface. The above results suggest that the effect of root proximity is important in the degradation of pyrene in ryegrass growing soil. © 2012.


Zhang M.-K.,Zhejiang University | Zhang M.-K.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Chang Y.-C.,Zhejiang University
Huanjing Kexue/Environmental Science | Year: 2013

By comparing the current quality investigation data of cultivated soils in Zhejiang province with the past data, changing characteristics of organic matter and pH value of the soils in this province over last 50 years were analyzed. The results showed that content of organic matter and pH value of the cultivated soils changed greatly during past 50 years, and the changes varied with historical periods and soil types. From 1958 to 1980s, accumulation of soil organic matter was obvious, soil organic matter increased averagely by 40.34%, and the mean pH increased slightly by 0.05 of pH unit. From 1980s to 2008, the mean content of organic matter in paddy soils decreased by 5.58%. The changes of soil organic matter varied with distribution zones of the paddy soils. The mean content of organic matter of paddy soils in valley plain increased with time, and those in plain with water network, hilly area and coastal plain decreased with time. The mean contents of organic matter in fluvio-aquic soil and coastal saline soil in the year 2008 were 29.48% and 14.60% respectively higher than those in 1980s. As compared with those obtained at 1980s, the cultivated soil in this province have been significantly acidified in the past thirty years, the mean pH value declined by 0.25 of pH unit, and the decline of pH value of paddy soils was greater than those of fluvio-aquic soil and saline soil. Changes in fertilization structure and conversion of paddy fields to upland were thought as main causes of the changes in both soil organic matter and pH value.


Zhang M.,Zhejiang University | Zhang M.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Zhang H.,Zhejiang University
Journal of Environmental Sciences | Year: 2010

To evaluate the effects of long-term applications of phosphorus fertilizers on mobility of dissolved organic matter (DOM) and heavy metals in agricultural soils, a sandy soil and a loamy soil were spiked with ammonium phosphate at application rates of 0, 25, 50, 100, 250, and 500 mg P per kilogram of soil. A series of 15-cm long soil columns were constructed by packing incubated soils of varying concentrations of P. The soil columns were consecutively leached by simulated rainfalls for six cycles. The contents of water extractable organic carbon in both sandy and loamy soils increased significantly with increasing rates of P applications. Relatively high rates of P applications could induce a marked increase in DOM concentrations in the leachates, the effects were larger with the sandy soil rather than with the loamy soil. Applications of P changed the partitioning of trace metals in the soil solids and the soil solutions. The increased P application rates also seemed to elevate the leaching of Cu, Cd, and Zn from soils. The concentrations of Cu, Cd, and Zn in the leachates were positively correlated with DOM, probably due to the formation of metal-DOM complexes. In contrast, Pb concentrations in the leachates were negatively correlated with DOM, and decreased with increasing rates of P applications. The boosted leaching of DOM induced by high rates of P applications was probably due to the added phosphate ions competing for adsorption sites in the soil solids with the indigenous DOM. © 2010 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences.


Zhang M.,Zhejiang University | Zhang M.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2010

Contaminated surface dust is a worldwide problem, and concentration and mobilization of contaminants in the surface dust are among the most critical issues in environmental risk assessment. Urban coach stations are one of the most important public places where surface dust has a direct effect on people's health as a result of respiration, because of the small size of the particles and the effect of heavy metals on biochemical mechanisms, and especially because the metals can be bio-accumulated. In order to investigate the accumulation, possible sources and availability of heavy metals in the surface dust at different types of urban coach stations, 73 surface dust samples were collected from each of 73 coach stations in Zhejiang Province for characterization of the particle composition and accumulation of Pb, Zn, Cu, Cd, Cr, Ni, Hg, As, Se, Al, Fe, Mn, and Co. Chemical forms of Pb, Zn, Cu, Cd, Cr, Ni, Hg, Fe, Mn, and Co in representative samples were also characterized by a sequential extraction technique. Multivariate statistical techniques, including correlation analysis, principal component analysis (PCA), and cluster analysis, were applied to identify possible sources of heavy metals in the surface dusts and classify the coach stations in term of chemical components of the surface dusts. The particle analysis showed that coarse particles with size of >100μm composed the majority of the surface dusts in the urban coach stations in Zhejiang Province, and suggested that the surface dusts mostly originated from soil, construction materials, and garbage near the coach stations, and atmospheric deposition made little contribution to the surface dusts. The mean total concentrations of Pb, Zn, Cu, Cd, Cr, Ni, Hg, As, and Se in the surface dusts were 287.1, 424.0, 172.8, 1.21, 122.3, 54.4, 0.71, 16.00, and 2.07 mg · kg-1, respectively, and were significantly higher than background values of the elements in the soils of the Zhejiang, indicating that the surface dusts were heavily contaminated with the heavy metals. Three significant components were extracted by PCA, explaining 89.77% of total variance of the 13 elements. Aluminium, Fe, Mn, and Co were associated with lithogenic components and originated from soil particles (natural source). Lead, Zn, Cu, Cd, Cr, and Ni were possibly related to traffic exhaust and industrial pollution. Mercury, As, and Se were originated from multiple activities including coal combustion, traffic exhaust, and industrial pollution. Based on the chemical components of the surface dusts, the 73 coach stations could be classified into 5 groups. Chemical speciation results showed that the chemical forms of the metals in surface dusts varied with the elements, and the potential availability of the metals decreased in the sequence Zn, Mn, and Cd > Cu, Ni, and Hg > Pb, Cr, and Fe.


Xie X.,Zhejiang University | Liao M.,Zhejiang University | Liao M.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Ma A.,Zhejiang University | And 3 more authors.
Chinese Journal of Geochemistry | Year: 2011

To assess the effects of single and combined pollution of cadmium (Cd) and mercury (Hg) on soil microbial community structural and functional diversities, an incubation experiment was conducted, by employing two soils, namely, the marine sediment silty loam soil and the yellowish-red soil, in which five levels of Cd, Hg and Cd and Hg in combination were added. After being incubated for 56 days, the phospholipid fatty acids (PLFAs) profile and sole carbon source utilization pattern (BIOLOG) of the samples were tested. The results showed that the composition of the microbial communities changed significantly at different levels of metals application. The principal component analyses (PCA) of PLFAs indicated that the structure of the microbial community was also significantly altered with increasing levels of metals, with increasing PLFAs biomarkers for fungi and actinomycetes, and increasing ratio of Gram-positive to Gram-negative bacteria. Sole carbon source utilization pattern analysis revealed that single and combined application of Cd and Hg inhibited significantly the functional activity of soil microorganisms, the functional diversity indices [Richness (S), Shannon-Wiener indices (H) and Evenness (EH)] were significantly lower in polluted soils than those in non-polluted soils, which also significantly altered with increasing levels of metals. PCA for the sole carbon source utilization pattern also indicated that the metal contamination could result in a variable soil microbial community. The results revealed that the combination of Cd and Hg had higher toxicity to soil microbial community structural and functional diversities than the individual application of Cd or Hg. © 2011 Science Press, Institute of Geochemistry, CAS and Springer-Verlag Berlin Heidelberg.


Zong Y.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Xiao Q.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition | Lu S.,Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition
Science of the Total Environment | Year: 2016

Black carbon (BC) and total carbon (TC) concentrations in urban topsoils and vertical profiles from steel industrial city, Anshan, Northeastern China, were determined. A total of 115 topsoil samples and 4 soil profiles were collected, in which the BC concentrations were determined using chemical oxidation technique. The BC concentrations in urban topsoils are in the range of 1.86 to 246.46gkg-1 with an average of 33.86gkg-1. Both BC and TC concentrations decrease sharply with soil depth, whereas BC/TC ratio shows a little variation with depth. The spatial distribution of BC in urban topsoils reveals that the BC concentration is much higher in the northern part of the city, which is consistent with the steel production. The distribution factors (DF) of BC are the highest in 1000-500 and 500-250μm size fractions, while the lowest in 50-2μm fraction. The mass loading of BC in 250-50 and 50-2μm size fractions accounts for 76.2% of bulk soil, indicating these two size fractions responsible for BC accumulation in soils. Enrichment factor (EF) of BC in urban topsoils ranges from 0.92 to 122.01 with an average of 16.76, indicating that the urban topsoils studied are moderately or severely accumulated by the BC. Strong correlation is found between BC and pollution load index (PLI) of heavy metals, indicating the possibility of similar sources of BC and heavy metals in soils. The BC/TC ratio in soils ranges from 0.45 to 0.97, with an average of 0.75. The BC/TC ratio shows the mixed sources of BC derived from fossil fuel combustion and vehicle emissions. The BC concentration and BC/TC ratio may reflect the degree of industrial activities and pollution sources in urban soils. The study demonstrated that BC is an effective indicator of degree and "hotspots" of heavy metals pollution in urban soils. © 2016 Elsevier B.V.

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