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Jie Jiang,
Ni Li,
Yan Shen,
Jibin Liu,
Li Liu,
Jiangbo Du,
Yu Lei,
Yang Wen,
Lin Yang,
Lanwei Guo,
Kai Zhang,
Fulin Qiang, Sumin Wang,
Zhibin Hu,
Min Dai,
Hongbing Shen
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ABSTRACT: OBJECTIVE: Human leukocyte antigens (HLA) play an important role in presenting virus antigens to immune cells that are responsible for the clearance of virus-infected cells and tumor cells. Herein, we evaluated whether genetic variants of HLA-DP and HLA-DQ are associated with cervical cancer risk. METHODS: We genotyped four single nucleotide polymorphisms (SNPs) in HLA-DP (rs3077 and rs9277535) and HLA-DQ (rs2856718 and rs7453920) in a two-stage case-control study with a total of 2317 cervical cancer cases and 2109 cancer-free controls using TaqMan allelic discrimination assay. RESULTS: We found consistently significant associations of HLA-DP rs3077 and rs9277535 with increased risks of cervical cancer (dominant genetic model: adjusted OR=1.51, 95% CI=1.32-1.71 for rs3077; adjusted OR=1.29, 95% CI=1.12-1.49 for rs9277535). When combining the effects of HLA-DP rs3077 and rs9277535, subjects carrying "≥1" variant alleles had a 1.55-fold increased risk of cervical cancer (95% CI=1.32-1.81), compared with those carrying "0" variant allele. And cervical cancer risk significantly increased with the increasing number of variant alleles of the two SNPs in a dose-dependent manner (P for trend=4.33×10-10). However, there were no significant associations for HLA-DQ rs2856718 and rs7453920 in our population. CONCLUSIONS: These findings indicate that HLA-DP rs3077 and rs9277535 were candidate susceptibility markers for cervical cancer in Chinese females. Further validation studies with different ethnic background, biological function analyses and especially HPV typing together were needed.
Gynecologic Oncology 02/2013; · 3.89 Impact Factor
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ABSTRACT: Based on the total phosphorous (TP) concentration in sediment core, the TP concentration in lake water quantitatively reconstructed
from fossil diatoms and diatom-TP transfer function in the Longgan Lake during the last 200 years, the temperature and precipitation
data from meteorological observation for the last 50 years, the temperatures and precipitation sequences of climate simulation
for the last 200 years, as well as the amount of the agricultural phosphate fertilizer in Longgan area for nearly 50 years,
the characteristic and the law of the nutrient status evolution were analyzed, and the influence of the climatic factor, the
anthropologic factor and the aquatic biology factor on the nutrient status evolution and its mechanism were discussed for
the Longgan Lake during the last 200 years. The results showed that, in the nearly 200 years, the TP concentration in the
sediment core of the Longgan Lake gradually increased, its range of variation was situated between 330–580 mg/kg, the mean
value was 388 mg/kg, a nearly 30-year vibration adjustment period existed at 1950 around. The TP concentration in lake water
changed in a different way. Before 1950, it had a slow increasing tendency in fluctuated background, to 1950 around it reached
up to the mean value (52.18 μg/L), and vibrated and adjusted around the mean value, then it fast declined, its change range
was situated between 37.75–62.33 μg/L. The analyses indicated that, in the centennial time scale, the climate change was the
main controlling factor, while in the decadal time scale in the recent 50 years, human activities were the leading factors
for the nutrient status evolution of the Longgan Lake. 60% of the variability of the TP concentration in the sediments and
57% of that in lake water were due to human activities. The differentiation between phosphorus concentration in the sediment
and in the lake water reflected the response processes and the adjustment abilities of the lake aquatic ecosystems to the
lake nutrient level, implying the maintenance and the destruction of the balances between the algae and the aquatic plants,
as well as the corresponding accumulating characteristics of the phosphorus.
Science in China Series D Earth Sciences 05/2012; 49:193-202. · 1.59 Impact Factor
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ABSTRACT: Use of micellar mobile phases in reversed-phase liquid chromatography (RPLC) results in hydrophobic and electrostatic sites
for interaction. Modified stationary phases in micellar liquid chromatography (MLC) are structurally similar to biomembranes.
To confirm this we focused on the effects of the type and concentration of surfactant (Brij 35, SDS, and CTAB) and mobile
phase pH on the retention of antihypertensive drugs on modified C18 stationary phases. Quantitative retention-activity relationships are proposed for the drugs and the different surfactants
and compared with those obtained using aqueous–organic mobile phases. Finally, a correlation was obtained between the logarithm
of retention factors (log k) and the toxicity (LD50) of antihypertensive drugs.
Chromatographia 04/2012; 64(1):23-29. · 1.20 Impact Factor
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ABSTRACT: The δ
18O records of ostracode shells in sediments of core QH-2000 from Qinghai Lake can be used as a better proxy to reflect monsoon
changes. Low monsoon precipitation between 17.5 and 11 cal. ka BP is indicated by positive δ
18O values averaging 2.37‰. A fast shift in δ
18O from positive at 11 cal. ka BP to negative at 10 cal. ka BP indicates sharp increase of monsoon precipitation. An interval
of generally high monsoon precipitation is observed between 10 and 6 cal. ka BP with δ
18O values averaging −2.15‰. Decrease of monsoon precipitation between 6 and 2.5 cal. ka BP is indicated by positive δ
18O values. δ
18O keeps positive values averaging 3.0‰ between 2.5 and 0 cal. ka BP suggesting low high monsoon precipitation. The climatic
changes indicated by δ
18O records of ostracode shells in sediments of core QH-2000 from Qinghai Lake and our broader regional comparison show that
the climate in Qinghai Lake since the late Glacial is probably controlled by southwest monsoon other than southeast monsoon.
Chinese Science Bulletin 04/2012; 52(4):539-544. · 1.32 Impact Factor
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[show abstract]
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ABSTRACT: Based on the function relationship between the shell length ofLimnocythere inopinata and the salinity of its living water in Tibetan Plateau lakes, the paleosalinty of Qinghai Lake in the past 900 years was
reconstructed through the measurement of the adult body length ofLimnocythere inopinata. Meanwhile, the paleosalinity sequence of Qinghai Lake during the same period was rebuilt by the Sr/Ca ratio of the shell
ofEucypris inflata combined with the Sr/Ca ratio of living ostracod valves from the species of genusEucypris inflata and the host water. The paleosalinity results obtained by two different methods were compared and assessed in this paper.
To check the result, it was also contrasted with other historical climatic sequences of this area including tree ring and
ice core. It was shown that the paleosalinity sequence rebuilt by adult ostracod body length had high reliability, and the
paleosalinity reconstruction method by trace elements of ostracod shells was not suitable for Qinghai Lake. From the reconstructed
paleosalinty sequence of Qinghai Lake, it can be found that low salinity during 1160–1290 AD showed the humid climate condition
on the Mediaeval Warm Period in this area, while the high salinity during 1410–1540 AD, 1610–1670 AD and 1770–1850 AD which
was corresponding to the three cold pulses of the Little Ice Age with a dry climate condition. And the high salinity in the
latest several decades was consistent with recent warm and dry trends of the climate in this area. The good consistency of
the reconstructed palaeosalinity sequence and the precipitation sequence in this area rebuilt by tree ring proves the reconstruction
of past lake salinity is reliable.
KeywordsQinghai Lake-paleosalinity-last 200 years-quantitative reconstruction
Chinese Science Bulletin 04/2012; 49(7):730-734. · 1.32 Impact Factor
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ABSTRACT: The paleoclimate and paleoenvironment of Qinghai Lake indicated by a 16000-year pollen record are as follows. It was very
cold and dry before 15200 years. During the Late Glacial, the climate varied from colder and semiarid to cool and semi-humid
and fluctuated frequently but with little amplitude. Three cold events in the periods of 13400–13000, 11600–12000, and 11000–10400
aBP respectively correspond to the Oldest Dryas, Older Dryas and Younger Dryas events, whereas the two warm periods between
them, 12000–13000 and 11600–11000 aBP, respectively correspond to Bölling and Alleröd periods. The temperature increased abruptly
after the Younger Dryas event, and then the climate gradually turned to be warm and wet from warm and semiarid. In the Holocene,
the largest amplitude of cold event that occurred at ca. 8200 aBP is quite prominent. The Holocene climatic optimum culminated
at 6700 aBP. After 2100 aBP, the climate tended to be cold and dry, keeping on up to now. Palaeoclimatic evolution and events
of Qinghai Lake based on pollen assemblage and concentrations can be well parallel with the global climatic events.
Chinese Science Bulletin 04/2012; 47(22):1931-1936. · 1.32 Impact Factor
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ABSTRACT: Living ostracod and hydrochemical samples were collected synchronously from more than 50 lakes and small water body in the
eastern edge area of the Tibetan Plateau, Northern Tibetan, Southern Tibet and mid-Tibet. The comparison of the adult body
length ofLimnocythere inopinata and hydrochemical parameters of their habitats shows that a quantitative relationship exists between the adult body length
and salinity expressed as conductivity. An empirical formula to reconstruct paleosalinity is suggested first and applied to
salinity reconstruction of CE-2 core from Cuoe Lake, Tibet. The method is verified by comparing its outcome with results of
other environment reconstruction methods.
Science in China Series D Earth Sciences 04/2012; 44:316-323. · 1.59 Impact Factor
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ABSTRACT: With the accelerating development of new drugs, there is a great need for rapid and simple screening technologies for estimating With the accelerating development of new drugs, there is a great need for rapid and simple screening technologies for estimating
the potential toxicity of new compounds. LD50 determination is the main way to measure the acute toxicity of all types of substances. In this paper, a new in vitro method, the potential toxicity of new compounds. LD50 determination is the main way to measure the acute toxicity of all types of substances. In this paper, a new in vitro method,
biopartitioning micellar chromatography, was developed for predicting oral acute toxicity (LD50) based on the similar properties between biopartitioning micellar chromatography systems and biological barriers and extracellular biopartitioning micellar chromatography, was developed for predicting oral acute toxicity (LD50) based on the similar properties between biopartitioning micellar chromatography systems and biological barriers and extracellular
fluids. A second-order polynomial model (an LD50 model) has been obtained using the retention data of the dihydropyridine selective calcium channel antagonists to predict fluids. A second-order polynomial model (an LD50 model) has been obtained using the retention data of the dihydropyridine selective calcium channel antagonists to predict
the pharmacological toxicity of the same compounds. the pharmacological toxicity of the same compounds.
Chromatographia 04/2012; 70(5):685-690. · 1.20 Impact Factor
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ABSTRACT: Multifold palynological diversity indices calculated by pollen data of the Heqing deep drilling core are synthetically analyzed,
the results show that the plant diversity rapidly increased and its fluctuant amplitude and frequency evidently largened during
the stages of 2.729–2.608 Ma, 1.176–0.342 Ma and since 0.118 Ma respectively, while during the other periods the plant diversity
was relatively low with a gentle fluctuation. To discuss further the relation between ancient plant diversity and paleoenvironment,
it is considered that the plant diversity in the Heqing region lies on increase or decrease of vertical vegetational belts
in mountains around the studied area and richness of components of these vegetational belts, and is controlled by amplitude
of tectonic uplift of mountains and climatic changes. The high plant diversity during 2.729–2.608 Ma responded to the strong
uplift of mountains at the stage, while the plant diversity greatly increased and its fluctuant amplitude and frequency markedly
largened at about 1.176 Ma was obviously response to the Middle Pleistocene Transition. The plant diversity and its fluctuant
amplitude and frequency increased further at about 0.991 Ma may be superposably affected by both the Middle Pleistocene Transition
and the tectonic uplift. The plant diversity increased since 0.118 Ma may indicate that the southwest monsoon strengthened
and humid climate more fitted many kinds of plants to grow.
Chinese Science Bulletin 04/2012; 53(23):3686-3698. · 1.32 Impact Factor
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ABSTRACT: Based on multi-proxy analysis of pollen, carbonate, TOC, TN and δ 13C of organic matters, a high-resolution climatic evolution of Qinghai Lake since the Late Glacial Age is reconstructed. The
results indicate that the boundary between the Last Glacial Maximum and the Late Glacial Age is at about 18.2 cal.ka BP. The
warm and wet period, which began at about 15.4 cal.ka BP, culminated at 7.4 cal.ka BP and came to its end at about 4.5 cal.ka
BP. After that, the climate gradually became cold and dry. The multi-proxy analysis indicates that the climate fluctuated
greatly during the transitional period from the Late glacial Age to the Holocene, and this is in good accordance with that
reflected by deep sea cores of North Atlantic, ice cores of Greenland, lake sediments in Europe, loess sequences and Guliya
ice core in China. The climatic evolutional characteristic of the Qinghai Lake since the Late Glacial Age shows that the driving
force of the East-Asia Monsoon correlates with solar radiation on the ten-thousand-year scale.
Science in China Series D Earth Sciences 04/2012; 48(6):742-751. · 1.59 Impact Factor
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ABSTRACT: Combining with the diatom-based conductivity transfer function from Qing-hai-Xizang (Tibetan) Plateau lakes, the lake salinity
for the past 300 years was quantitatively reconstructed based on the analysis of diatom assemblages from a sediment core in
Chencuo Lake, southern Tibet. The distinct negative relationship between inferred conductivity and recorded lakelevels in
recent years suggests that the lake salinity can reflect the fluctuations of effective moisture of climate in lake area. The
salinity inferred from diatoms reveals several major hydrological episodes. An obvious desalination of lake water occurred
during the last cold interval of the Little Ice Age (about 1845–1885 AD), indicating a cold and moist climate. The lake salinity
presented a rapid increase trend since the middle 1960s, with a peak value and high amplitude of salinity variability in the
whole past 300 years. The low effective moisture inferred from the lake salinity may have contributed to the enhanced evaporation
by the continuous increase of temperature in recent years.
Science in China Series D Earth Sciences 04/2012; 47(6):522-528. · 1.59 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: A 12.87-m-long sediment core was retrieved from closed-basin Lake Daihai in the monsoon–arid transition zone of north-central
China. Oxides of major elements and their ratios normalized to Al in the AMS-14C-dated core were employed to evaluate chemical weathering intensity (CWI) in the lake drainage basin, which reflects hydrothermal
conditions in the study area. Lower CWI periods occurred prior to 14.5kaBP, and during the intervals ca. 11.7–10.3, 3.5–3.2,
2.6–1.7kaBP, and 1.2–0kaBP, indicating relatively low temperatures and moisture availability. Greater CWI during the intervening
periods ca. 14.5–11.7, 10.3–9.0, 3.2–2.6, and 1.7–1.2kaBP, with the maximum CWI at ca. 6.7–3.5kaBP, imply ameliorated
hydrothermal conditions in the lake basin, i.e. higher temperatures and precipitation. Exceptionally low CWI, associated with
high CaO/MgO ratio during ca. 9.0–6.7kaBP, suggests higher evaporation rates in the area under warmer temperature. Overall,
CWI displays in-phase variations with changes in organic matter (TOC, TN), carbonate (CaCO3) and pollen assemblages, all of which are related to variations in monsoon effective precipitation. High CWI indicates strong
monsoon-induced precipitation, whereas low CWI reflects a weak precipitation regime. The optimum hydrothermal status, recorded
by the strongest CWI and maximum monsoon effective precipitation during ca. 6.7–3.5kaBP defines the Holocene climate optimum
(HCO) in the Lake Daihai region. These results indicate that the HCO prevails after the early Holocene in the monsoon–arid
transition zone of north-central China. Temperature and precipitation variations during most of the Holocene, inferred from
the lake sediments, are due largely to insolation forcing. Dry but warm conditions ca. 9.0–6.7kaBP, however, probably reflect
the complex interactions between insolation and geography (e.g. altitude and local topography).
Journal of Paleolimnology 04/2012; 43(1):75-87. · 1.90 Impact Factor
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[show abstract]
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ABSTRACT: By measuring Sr/Ca ratios of the ostracod shells (Limnocthere cf. inopinata) in sediments of the Daihai Lake, and combined with Sr2+/Ca2+ ratios of the lake water, this paper obtained paleosalinity of the lake water. Vaporizing experiment of the lake water in
laboratory showed that there was a quantitative relationship between salinity and oxygen isotope. Using this relationship,
oxygen isotope values of the paleo-lake water were calculated. By measuring the oxygen isotope of the authigenic carbonate
in the lake’s sediments, and in combination with the oxygen isotope values of the paleo-lake water, the paleotemperature of
the lake water was calculated. Finally, based on these proxies, the paleoclimate in the lake basin was explored.
Science in China Series D Earth Sciences 04/2012; 45(9):792-800. · 1.59 Impact Factor
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ABSTRACT: In this paper, Lake Taihu, a large shallow freshwater lake in China, is chosen as an example of reconstruction of eutrophication
through the comparison between stable isotopes from dissolved nutrients and plants and water column nutrient parameters and
integration of multiple proxies in a sediment core from Meiliang Bay including TN, TP, TOC, C/N, δ
15N, δ
13C, etc. Differences in aquatic plant species and trophic status between East Taihu Bay and Meiliang Bay are indicated by their variations
in δ
13C and δ
15N of aquatic plants and δ
15N of NH4
+. A significant influence of external nutrient inputs on Meiliang Bay is reflected in temporal changes in δ
15N of NH4
+ and hydro-environmental parameters. The synchronous change between δ
13C and δ
15N values of sedimented organic matter (OM) has been attributed to elevated primary production at the beginning of eutrophication
between 1950 and 1990, then recent inverse correlation between them has been caused by the uptake of 15N-enriched inorganic nitrogen by phytoplankton grown under eutrophication and subsequent OM decomposition and denitrification
in surface sediments, indicating that the lake has suffered from progressive eutrophication since 1990. Based on the use of
a combination of stable isotopes and elemental geochemistry, the eutrophication of Meiliang Bay in Lake Taihu could be better
traced. These transitions of the lake eutrophication respectively occurring in the 1950s and 1990s have been suggested as
a reflection of growing impacts of human activities, which is coincident with the instrumental data.
Science in China Series D Earth Sciences 04/2012; 49:62-71. · 1.59 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Based on a multi-proxy investigation into the deep core of the Cuoe Lake in the middle of Tibetan Plateau, a 2.8 Ma paleoclimatic
and paleoenvironmental evolution is reconstructed. The result of magnetic stratum indicates that the lake basin was formed
at about 2.8 MaBP, while the multi-proxy analyses of lithology, grain size, magnetic susceptibility and geochemical elements
reveal that there have been three major environmental evolution stages and at least two intensive uplifts of the Tibetan Plateau
in the lake basin area, i.e. during 2.8-2.5 MaBP, the lake basin came into being as a result of the disaggregation of the
planation surface and rapid rising of the Tibetan Plateau. During 2.5-0.8 MaBP, with gradual uplift of the Tibetan Plateau,
the environment of this area was more effectively controlled by the climatic cycle of the alternative glacial-interglacial
stages. After 0.8 MaBP, the middle part of the Plateau accelerated its uplift and entered cryoshere.
Science in China Series D Earth Sciences 04/2012; 47(11):1025-1034. · 1.59 Impact Factor
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[hide abstract]
ABSTRACT: We explored the use of carbon and nitrogen isotope ratios (δ13C, δ15N) in sediment organic matter as proxy indicators of historical changes in the trophic state of Lake Taihu, the third largest
freshwater lake in China. Stable isotope signatures in four sediment cores spanning the 20th century were compared with instrumental
records of lake-water trophic state. The comparative study shows that, between ∼
∼1950 and 1990 AD, the δ13C and δ15N of sediment organic matter throughout Lake Taihu increased along the trophic gradient from oligotrophy to eutrophy due to
biological isotopic fractionation. However, in the 1990s, the trophic state of Lake Taihu diverged into two different trophic
systems, a hypereutrophic western Lake Taihu dominated by blue-green algae and a mesoeutrophic eastern Lake Taihu dominated
by vascular aquatic plants. During the post-1990 AD shift from mesoeutrophic to hypereutrophic state in western Lake Taihu,
organic matter δ13C and δ15N decreased sharply in response to pronounced shifts in the aquatic ecosystem. The results indicate that 13C-depleted phytoplankton replaced macrophytes in western Lake Taihu. δ15N values in western Lake Taihu also decreased because of N2 fixation by cyanobacteria in this highly productive ecosystem. By contrast, in eastern Lake Taihu, organic matter δ13C and δ15N values show a post-1990 AD trend towards slightly lower values, but they remain higher than the long-term average. This
recent 13C–enrichment of organic matter indicates that periods of high productivity in the restricted eastern sub-basin of Lake Taihu
limited aqueous CO2 availability, causing a decrease in isotopic discrimination during photosynthesis. After ∼
∼1990 AD, organic matter δ15N values for eastern Lake Taihu only dropped slightly, suggesting that the contribution of phytoplankton to the sediment organic
matter increased slightly. Taken together, the results indicate that nitrogen-fixing cyanobacteria probably played a much
smaller role in primary productivity in this part of eastern Lake Taihu, compared with western Lake Taihu. Despite the complexity
of carbon and nitrogen cycles in lakes, the agreement between the stable isotope signatures and instrumental records for Lake
Taihu suggests that δ13C and δ15N in sediment organic matter are capable of recording important shifts in the spatial and temporal evolution of lake-water
trophic state.
Hydrobiologia 04/2012; 563(1):19-29. · 1.78 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The sedimentary environment change, trophic evolution and heavy metals pollution history of the northern Taihu Lake in the
last 100 years are studied according to the sedimentary geochemical proxies of the core sediments, such as grain size, nutrients,
heavy metals, diatom, etc. The nutrients in the sediments depended mainly on the lake internal circulation and the heavy metals were from natural geogenic
sources before the 1920s, which were not influenced by human activities generally, and grain size was one of the key factors
influencing heavy metals content in the sediments. The alternation of manner and strength of human activities in Taihu Lake
catchment before and after the 1920s made the lake sediments coarser, and hence heavy metals and TP content decreased contrasted
with that before the 1920s. TP content in sediments and water increased from the 1950s to late 1970s due to anthropogenic
pollutants discharge, and the lake belonging to mesotrophic state. TN and TOC content and C/N ratio increased due to the increasing
external pollutants into Taihu Lake by human activities, TP content also increased obviously in water and sediments, and the
diatom association was dominated by eutrophic species since the late 1970s, indicating the eutrophication state of Taihu Lake
in this period. Meanwhile the increasing in heavy metals content, such as Cu, Mn, Ni, Pb and Zn, and their proportion of valid
fractions in the sediments indicates that they all result from human pollutants since the late 1970s. The heavy metals in
the surface sediments have certain potential biological toxicity due to the higher SEM/AVS ratio.
Science in China Series D Earth Sciences 04/2012; 49:82-91. · 1.59 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The chronology of a gravity core sediment from Longgan Lake center was defined by210Pb, combining with historic events recorded by document and sediment. The relationship between vegetation, soil erosion and
lake nutrient state was discussed based on pollen, magnetic parameters, diatoms, phosphorus and pigments. The results show
that the lake has undergone twice obvious transformations from oligotrophic to mesotrophic condition. Two eutrophications
occurring at about 1768AD and the beginning of the 20th century respectively were related to external nutrient loading increase
resulting from the enhanced human activities in the lake catchment. It is probable that strength of human actions in historic
periods was influenced more or less by climatic changes. The lake eutrophication presented a more serious tendency because
of the wide use of chemical fertilizer, reclamation of wetland and wetland vegetation destruction around the lake in the last
40 years.
Science in China Series D Earth Sciences 04/2012; 45(8):709-718. · 1.59 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Metals in lacustrine sediment have both anthropogenic and natural sources. Because of intensified human activities, the anthropogenic
input of metal elements has exceeded the natural variability. How to distinguish the anthropogenic sources in lake sediments
is one of the tasks in environmental management. The authors present a case study, which combined the geochemical and statistical
methods to distinguish the anthropogenic sources from the natural background. A 56cm core (core DJ-5) was collected from
Dongjiu Lake, Taihu Lake catchment, China. The concentration distributions of Al, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg,
Mn, Na, Ni, Pb, Sr, Ti, V and Zn in core DJ-5 indicated that Dongjiu Lake had serious Cd pollution, and the concentrations
of Cr, Cu, Pb, Mn and Zn had also exceeded the Chinese State Standards of Soil Environmental Quality in the upper layer of
the core. Using Al as a reference element, the other metals were normalized and compared with their baselines to calculate
the enrichment factors (EFs). The principal component analysis (PCA) of metal concentrations was performed using ViSta6.4.
The results of EFs and PCA indicated that the concentration variations of Cd, Cu, Pb, Mn and Zn were mainly caused by the
anthropogenic sources, and the concentration variations of Cr and Ni were influenced by both the anthropogenic and natural
factors, while the other metals were mainly derived from the natural sources. Intensified human activities within the lake
catchment area resulted in the increase of heavy metal inputs directly and the acceleration of erosion which caused other
metal elements to deposit in the aquatic environment. The results of this work will be useful in probing changes forced by
humans in the lake environment and in adjusting human activity in restoring the lake environment.
Environmental Geology 04/2012; 52(8):1467-1474. · 1.13 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Ostracods are small bivalved aquatic crustaceans. They secrete shells of low-Mg calcite that are often preserved in lake sediments.
Recent work has shown that the uptake of trace elements (especially Mg and Sr) into the shell may be a function of the salinity
and temperature of the host water. We measured Sr/Ca ratios in living ostracod valves from the species of genusLimnocythere cf. inopinata and Sr2+/Ca2+ ratios of the host water to calculate distribution coefficient of genusLimnocythere cf. inopinata in the Daihai Lake. A function for Sr2+/Ca2+ ratio and salinity was established by measuring a series of Sr2+/Ca2+ ratios and salinities of the lake water in different places of the Daihai Lake. Finally paleosalinities of the lake water
were quantitatively reconstructed by the Sr/Ca ratios of ostracod shells of the same species in sediment core of the Daihai
Lake.
Keywordsquantitative reconstruction-paleosalinity-Daihai Lake
Chinese Science Bulletin 04/2012; 46(1):73-76. · 1.32 Impact Factor
