The Chinese family farm is the most important new micro subject in the construction and development of modern agriculture in China. The investigation and analysis of the actual situation of Hubei Province showed that ...The Chinese family farm is the most important new micro subject in the construction and development of modern agriculture in China. The investigation and analysis of the actual situation of Hubei Province showed that since the implementation of the household contract management system in rural areas, the family farm has followed the track of gradual development, breakthrough development and normal standardization development. In order to promote the family farm to develop rapidly, orderly and healthily, work must be well done to land circulation, scale management, financial support, financial subsidy, cultivation of leading talents and professional farmers, and providing all-round services.展开更多
The goal of land consolidation in China is still to develop agricultural production.The study of landscape effects of land consolidation projects(LCPs)faces many difficulties because of the lack of government's in...The goal of land consolidation in China is still to develop agricultural production.The study of landscape effects of land consolidation projects(LCPs)faces many difficulties because of the lack of government's interest and data.This paper,taking Tianmen City of Hubei Province in Central China as an example,presents a methodology for analyzing landscape effects of LCPs by GIS and Fragstats3.3.It describes landscape effects with indexes of Patch Density(PD),Largest Patch Index(LPI),Landscape Shape Index(LSI),Interspersion and Juxtaposition Index(IJI),Aggregation Index(AI),and Shannon's Diversity Index(SHDI),showing more regular shape,simpler structure and less habitat diversity after LCPs.It computes ten landscape indexes of four categories of patches including Cultivated Land,Road,Water Channel,and River and Pond.The indexes show that 1)cultivated land becomes more fragmental in patch area,less irregular in patch shape and more concentrated in block;2)the transport capacity of roads and irri-gation and drainage capacity of water channels have been improved;3)the landscape change of river and pond can be summarized as decreasing scale,more regular shape,reducing connectivity and diversity of the class.LCPs can facili-tate agricultural production as well as protect cultivated land and food security.However,it is doubted that the increase of cultivated land from LCPs results from the reducing in landscape diversity of water area.展开更多
The genus Beris Latreille is newly reported from Hubei with one new species Beris shennongana, sp. nov., and one known species, Beris hirotsui Ouchi, 1943.
From June 2003 to June 2004, an investigation on the life cycle, production and trophic basis of dominant species of macrozoobenthos community in a second-order river of the Hanjiang River basin, Hubei, China was card...From June 2003 to June 2004, an investigation on the life cycle, production and trophic basis of dominant species of macrozoobenthos community in a second-order river of the Hanjiang River basin, Hubei, China was carded out. The results showed that the dominant species Leptophlebia sp. and Ephemera sp. appeared to develop two generations per year, and there was a small overlap in the two generations of both species. The pupation of Leptophlebia sp. mainly occurred in autumn and winter, while pupation of Ephemera sp. mainly took place in summer and winter. The standing stocks of the Leptophlebia sp. population and Ephemera sp. population had two peaks in a year. The cohort production and cohort P/B ratio of the Leptophlebia sp. population estimated by size frequency method were 19.018 1 g/m^2.a and 5.7 respectively, while its annual production and P/B ratio were 38.036 2 g/m^2.a and 11.4. The cohort production and cohort P/B ratio of the Ephemera sp. population were 38.015 9 g/m^2.a and 5.9, while its annual production and P/B ratio were 76.031 8 g/m^2.a and 11.8.展开更多
[Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Pr...[Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Province where rice blast occurs frequently,60 isolates which were pathotyped against two sets of host differentials:Chinese host differentials and CO39 NILs,were obtained.Then,20 pathotypes with the six indica host differentials(CO39 NILs) were observed,while 13 pathotypes in four race groups were observed out of the same single spore isolates with Chinese host differentials which consists of three indica cultivars and four japonica cultivars.The diversity of the pathotypes of M.grisea populations tested by CO39 NILs was 2.54 and the pathotype 137.1 occurred at predominantly high frequency(21.67%).The diversity of physiological races of M.grisea populations tested by Chinese host differentials was 1.22 and the race group ZA occurred at predominantly high frequency(73.33%).The diversity of physiological races of M.grisea in Chongyang and Yuan'an were also calculated.Overall,the diversity of pathotypes of M.grisea in Yuan'an was higher than that in Chongyang with the two sets of the host differentials.[Conclusion] This study provided current information on the pathotype spectrum of M.grisea populations in the rice fields of Hubei Province to allow the formulation of viable strategies for blast resistance breeding programs in Hubei Province.展开更多
Rural settlements are the main carriers of agriculture, rural areas and farmers; thus, optimizing the production and living space of rural settlements is highly significant to rural development. Taking the effective a...Rural settlements are the main carriers of agriculture, rural areas and farmers; thus, optimizing the production and living space of rural settlements is highly significant to rural development. Taking the effective allocation of resources as the starting point, a suitability evaluation system of rural settlements, based on accessibility of production and living, was proposed in this study to provide scientific basis for the optimization of production and living space. The accessibility of production and living was measured by an im- proved two-step floating catchment area method, which considered proximity and availability based on the inclination of rural residents. The suitability evaluation system consisted of traditional suitability evaluation and newly proposed limiting factor identification based on the loss score proportion of suitability. Tingzu Town of Hubei Province, China, was chosen as the case study area. Based on the re- suits of the suitability evaluation system, corresponding suggestions on rural land consolidation, industry division, as well as the layout of health care and education facilities were proposed to optimize the production and living space of rural settlements in Tingzu Town. It is found that the suitability evaluation based on accessibility of production and living is more scientific and accurate than the traditional ones which significantly overestimate production and living convenience. Moreover, the limiting factor identification can help us put forward suggestions according to local conditions and bring about the highly targeted optimization of production and living space of rural settlements.展开更多
This study aimed to evaluate emerging trends of drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) among 290 former blood donor HIV-1 inf...This study aimed to evaluate emerging trends of drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) among 290 former blood donor HIV-1 infected patients in Hubei, China, from 2004 to 2006, all of whom had received anti-HIV-1 therapy. The presence of NRTI- and NNRTI-associated mutations were established by sequencing; genotypic and predicted phenotypic drug resistance were evaluated using HIVdb Program version 5.0.1 (http://hivdb.stanford.edu/ pages/algs/HIVdb.html). Genotypic drug resistance analysis showed significant increases in percentages of patients carrying HIV-1 strains with M41L, T215Y/F, D67N, K103N, G190A/S, Y181C/F or L210W mutations. Of the variants' predicted phenotypic drug resistance, highly significant increases were detected in percentages of patients carrying HIV-1 with high resistance to zidovudine (AZT) or stavudine (D4T) in NRTIs, and to delavirdine (DLV), efavirenz (EFV) or nevirapine (NVP) in NNRTIs; intermediate resistance to abacavir (ABC), AZT, D4T, didanosine (DDI) or tenofovir disoproxil fumarate (TDF) in NRTIs, and to etravirine (ETR) in NNRTIs; and low and potential low resistance to lamivudine (3TC), ABC, emtricitabine (FTC) or TDF in NRTIs, and to ETR in NNRTIs.展开更多
Lake Lop Nur is located in the eastern part of the Tarim Basin in Xinjiang,northwestern China.A 220-cm-long sediment core was collected from the center of the ear-shaped depression forming the basin and dated with AMS...Lake Lop Nur is located in the eastern part of the Tarim Basin in Xinjiang,northwestern China.A 220-cm-long sediment core was collected from the center of the ear-shaped depression forming the basin and dated with AMS^(14)C.Grain size,total organic matter(TOC),total nitrogen(TN),and TOC/TN(C/N)analyses were used to reconstruct climatic conditions from 13.0 to 5.6 cal ka BP.The results showed fi ve main climatic stages.Zone I(13.0–11.3 cal ka BP)was a wet–dry environment,whereas Zone II(11.3–8.9 cal ka BP)consisted of a primarily wet environment.Zone III(8.9–7.7 cal ka BP)was subdivided into Zone IIIa(8.9–8.2 cal ka BP)that indicated lake constriction and dry climate,and Zone IIIb(8.2–7.7 cal ka BP)in which the proxies indicated wet conditions.In Zone IV(7.7–6.6 cal ka BP),the climate presented a bit wet conditions.In Zone V(6.6–5.6 cal ka BP),abundant glauberite is present in the sediment and silt dominates the lithology;these results indicate the lake shrank and the overall climate was dry.Abrupt environmental events were also identifi ed,including six dry events at 11.0,10.5,9.3,8.6,8.2,and 7.6 cal ka BP and one fl ood event from 7.8 to 7.7 cal ka BP in the Early–Middle Holocene.展开更多
Research on the optical characteristics of water color constituents in Chagan Lake of Jilin Province,Northeast China was carried out in order to investigate the variability of the spectra absorption parameters as inpu...Research on the optical characteristics of water color constituents in Chagan Lake of Jilin Province,Northeast China was carried out in order to investigate the variability of the spectra absorption parameters as inputs to bio-optical models and remote sensing algorithms for converting observed spectral signals into water quality information.Samples of total particulates,non-algal particles and colored dissolved organic matter (CDOM) were first prepared by quantitative filter technique (QFT) and then absorption coefficients of these color producing agents were determined by spectrophotometry.Spectral characteristics of absorption coefficients by total particulate matter,spectral specific absorption dependency on chlorophyll concentration (Chl-a) of phytoplankton,spectral absorption slopes variation for CDOM and non-algal particles and their corresponding reasons were examined and clarified over five months of 2009 and 2010 in this study.Results suggest that total particulate spectral absorption in Chagan Lake is mainly dominated by non-algal particles in most cases,but phytoplankton could be the dominant contributor when chlorophyll concentration is high (up to 84.48 mg/m3 in autumn 2010).The specific absorption coefficients of phytoplankton particulate (a*ph(λ)) dependency on Chl-a is significantly variable due to relative contributions of package effect and accessory pigments,and the parameters of power function are clearly biased on a long time span.The sources of variability in spectral absorption slopes of CDOM and non-algal particles are mainly attributed to the changing proportions of high molecular weight humic acids and mineral suspended sediments in waters,respectively.展开更多
The aquatic ecosystem maybe significantly affected by polycyclic aromatic hydrocarbons(PAHs) released from fresh water sediments. In order to protect biodiversity, the spatial distribution and sources of PAHs in the s...The aquatic ecosystem maybe significantly affected by polycyclic aromatic hydrocarbons(PAHs) released from fresh water sediments. In order to protect biodiversity, the spatial distribution and sources of PAHs in the sediment of Wolong Lake in Northeast China were studied. A total of 17 surface sediment samples were collected and 12 PAHs were analyzed. The results were as follows. The concentration of total PAHs(TPAHs) ranged between 1412.9 μg/kg and 3948.3 μg/kg(dry weight). Indeno [1, 2, 3-c, d] pyrene was the dominant contaminant which accounted for 87%–98% of TPAHs. Diagnostic ratios of PAHs and principal component analysis showed that biomass combustion and vehicle emissions were likely to be the dominant sources of PAHs in the sediment. PAHs can be considered safe in the context of environmental and human health protection, based on the overall toxicity. Individual PAHs were positively correlated with total organic carbons. These results will be helpful to control PAHs and protect the aquatic ecosystem in the lake.展开更多
The fluvio-lacustrine sedimentary sequences in the Nihewan Basin, northern China, are important for studying Quaternary land mammal evolution and Paleolithic settlements in the high-latitude temperate East Asia. Here ...The fluvio-lacustrine sedimentary sequences in the Nihewan Basin, northern China, are important for studying Quaternary land mammal evolution and Paleolithic settlements in the high-latitude temperate East Asia. Here we report new magnetostrati- graphic results that constrain age of the Hougou Paleolithic site in this basin. Magnetite and hematite were identified as carriers of the characteristic remanent magnetizations, with the former being dominant. Magnetic polarity stratigraphy shows that the Hougou sequence recorded the very late Matuyama reverse chron and the Brunhes normal chron. The age of the Hougou Paleolithic site was estimated to be 395 ka based on an averaged rate of sediment accumulation. The combination of our mag- netostratigraphy and previously published chronological data for early Paleolithic or human sites in the high-latitude northern China may document a persistent colonization of the hostile high-latitude areas of the eastern Old World during the mid- die-early Pleistocene.展开更多
Seoul virus(SEOV), which is predominantly carried by Rattus norvegicus, is one of the major causes of hemorrhagic fever with renal syndrome(HFRS) in China. Hubei province, located in the central south of China, has ex...Seoul virus(SEOV), which is predominantly carried by Rattus norvegicus, is one of the major causes of hemorrhagic fever with renal syndrome(HFRS) in China. Hubei province, located in the central south of China, has experienced some of the most severe epidemics of HFRS. To investigate the mitochondrial DNA(mt DNA)-based phylogenetics of wild rats in Hubei, and the relationship with SEOV infection, 664 wild rats were captured from five trapping sites in Hubei from2000–2009 and 2014–2015. Using reverse-transcription(RT)-PCR, 41(6.17%) rats were found to be positive for SEOV infection. The SEOV-positive percentage in Yichang was significantly lower than that in other areas. The mt DNA D-loop and cytochrome b(cyt-b) genes of 103 rats were sequenced.Among these animals, 37 were SEOV-positive. The reconstruction of the phylogenetic relationship(based on the complete D-loop and cyt-b sequences) allowed the rats to be categorized into two lineages, R. norvegicus and Rattus nitidus, with the former including the majority of the rats. For both the D-loop and cyt-b genes, 18 haplotypes were identified. The geographic distributions of the different haplotypes were significantly different. There were no significant differences in the SEOVpositive percentages between different haplotypes. There were three sub-lineages for the D-loop,and two for cyt-b. The SEOV-positive percentages for each of the sub-lineages did not significantly differ. This indicates that the SEOV-positive percentage is not related to the mt DNA D-loop or cyt-b haplotype or the sub-lineage of rats from Hubei.展开更多
Santanghu area in northeastern Xinjiang region of Northwest China is an important component of the Central Asian Orogenic Belt(CAOB), in which the dynamic mechanism of Permian magmatism is controversial. In Santanghu ...Santanghu area in northeastern Xinjiang region of Northwest China is an important component of the Central Asian Orogenic Belt(CAOB), in which the dynamic mechanism of Permian magmatism is controversial. In Santanghu area is exposed a thick succession of the Middle Permian basalts, including a small amount of picritic basalts and andesites, known as the Tiaohu Formation. The picritic basalts contain cumulate olivine, and have whole-rock Mg# up to 0.68–0.77; the basalts exhibit porphyritic or doleritic textures, and have relatively low Mg# of 0.41–0.54, typical of evolved magmas. The mafic-ultramafic rocks of the Tiaohu Formation are slightly enriched in Light Rare Earth Elements(LREEs), and exhibit negative Nb and Ti anomalies. They also have high Ti O2 content, and Nb/Y and Zr/Yb ratios greater than those of island arc volcanic rocks. Relatively low initial Sr isotopic ratios and high positive εNd(t) and εHf(t) values argue against contamination by ancient continental crust, and suggest formation of the Tiaohu Formation by partial melting of relatively refractory depleted lithospheric mantle that underwent metasomatism and extraction by fluid from the subducted slab. In addition, up to 38% olivine in picritic basalts indicates high-degree partial melting of lithospheric mantle, and the underlying Lucaogou Formation contains fragments of ultra-alkaline magmatic rocks that originated in the deep mantle. These observations imply wide-spread underplating in Santanghu area, which may have been associated with a mantle plume.展开更多
NEW TAOIST LEADERLi Guangfu,previously Vice Chairman of the China Taoist Association(CTA),was elected the new CTA chairman during the association’s national congress in late June.Li was born in central China’s Hub...NEW TAOIST LEADERLi Guangfu,previously Vice Chairman of the China Taoist Association(CTA),was elected the new CTA chairman during the association’s national congress in late June.Li was born in central China’s Hubei Province in 1955.He also headed the Taoist Association of Wudang Mountain in Hubei, a hub location for China's Taoist culture.展开更多
基金Supported by the Social Science Funding Project of Hubei Province(201590)~~
文摘The Chinese family farm is the most important new micro subject in the construction and development of modern agriculture in China. The investigation and analysis of the actual situation of Hubei Province showed that since the implementation of the household contract management system in rural areas, the family farm has followed the track of gradual development, breakthrough development and normal standardization development. In order to promote the family farm to develop rapidly, orderly and healthily, work must be well done to land circulation, scale management, financial support, financial subsidy, cultivation of leading talents and professional farmers, and providing all-round services.
基金Under the auspices of National Natural Science Foundation of China (No. 70673097)
文摘The goal of land consolidation in China is still to develop agricultural production.The study of landscape effects of land consolidation projects(LCPs)faces many difficulties because of the lack of government's interest and data.This paper,taking Tianmen City of Hubei Province in Central China as an example,presents a methodology for analyzing landscape effects of LCPs by GIS and Fragstats3.3.It describes landscape effects with indexes of Patch Density(PD),Largest Patch Index(LPI),Landscape Shape Index(LSI),Interspersion and Juxtaposition Index(IJI),Aggregation Index(AI),and Shannon's Diversity Index(SHDI),showing more regular shape,simpler structure and less habitat diversity after LCPs.It computes ten landscape indexes of four categories of patches including Cultivated Land,Road,Water Channel,and River and Pond.The indexes show that 1)cultivated land becomes more fragmental in patch area,less irregular in patch shape and more concentrated in block;2)the transport capacity of roads and irri-gation and drainage capacity of water channels have been improved;3)the landscape change of river and pond can be summarized as decreasing scale,more regular shape,reducing connectivity and diversity of the class.LCPs can facili-tate agricultural production as well as protect cultivated land and food security.However,it is doubted that the increase of cultivated land from LCPs results from the reducing in landscape diversity of water area.
基金funded by Beijing Financial Budget Index [2008] No. 0178Beijing Nova Project (No.2006A50)
文摘The genus Beris Latreille is newly reported from Hubei with one new species Beris shennongana, sp. nov., and one known species, Beris hirotsui Ouchi, 1943.
文摘From June 2003 to June 2004, an investigation on the life cycle, production and trophic basis of dominant species of macrozoobenthos community in a second-order river of the Hanjiang River basin, Hubei, China was carded out. The results showed that the dominant species Leptophlebia sp. and Ephemera sp. appeared to develop two generations per year, and there was a small overlap in the two generations of both species. The pupation of Leptophlebia sp. mainly occurred in autumn and winter, while pupation of Ephemera sp. mainly took place in summer and winter. The standing stocks of the Leptophlebia sp. population and Ephemera sp. population had two peaks in a year. The cohort production and cohort P/B ratio of the Leptophlebia sp. population estimated by size frequency method were 19.018 1 g/m^2.a and 5.7 respectively, while its annual production and P/B ratio were 38.036 2 g/m^2.a and 11.4. The cohort production and cohort P/B ratio of the Ephemera sp. population were 38.015 9 g/m^2.a and 5.9, while its annual production and P/B ratio were 76.031 8 g/m^2.a and 11.8.
基金Supported by the Key Project of the National 11th Five-Year Plan of China (2006BADO8A04-06)
文摘[Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Province where rice blast occurs frequently,60 isolates which were pathotyped against two sets of host differentials:Chinese host differentials and CO39 NILs,were obtained.Then,20 pathotypes with the six indica host differentials(CO39 NILs) were observed,while 13 pathotypes in four race groups were observed out of the same single spore isolates with Chinese host differentials which consists of three indica cultivars and four japonica cultivars.The diversity of the pathotypes of M.grisea populations tested by CO39 NILs was 2.54 and the pathotype 137.1 occurred at predominantly high frequency(21.67%).The diversity of physiological races of M.grisea populations tested by Chinese host differentials was 1.22 and the race group ZA occurred at predominantly high frequency(73.33%).The diversity of physiological races of M.grisea in Chongyang and Yuan'an were also calculated.Overall,the diversity of pathotypes of M.grisea in Yuan'an was higher than that in Chongyang with the two sets of the host differentials.[Conclusion] This study provided current information on the pathotype spectrum of M.grisea populations in the rice fields of Hubei Province to allow the formulation of viable strategies for blast resistance breeding programs in Hubei Province.
基金Under the auspices of National Scientific and Technical Supporting Programs During 12th Five-year Plan(No.2012BAJ22B02)
文摘Rural settlements are the main carriers of agriculture, rural areas and farmers; thus, optimizing the production and living space of rural settlements is highly significant to rural development. Taking the effective allocation of resources as the starting point, a suitability evaluation system of rural settlements, based on accessibility of production and living, was proposed in this study to provide scientific basis for the optimization of production and living space. The accessibility of production and living was measured by an im- proved two-step floating catchment area method, which considered proximity and availability based on the inclination of rural residents. The suitability evaluation system consisted of traditional suitability evaluation and newly proposed limiting factor identification based on the loss score proportion of suitability. Tingzu Town of Hubei Province, China, was chosen as the case study area. Based on the re- suits of the suitability evaluation system, corresponding suggestions on rural land consolidation, industry division, as well as the layout of health care and education facilities were proposed to optimize the production and living space of rural settlements in Tingzu Town. It is found that the suitability evaluation based on accessibility of production and living is more scientific and accurate than the traditional ones which significantly overestimate production and living convenience. Moreover, the limiting factor identification can help us put forward suggestions according to local conditions and bring about the highly targeted optimization of production and living space of rural settlements.
基金The Key Projects in the National Science & Technology Pillar Program during the Eleventh Five-Year Plan Period of China (2008ZX10001-002)the Major Science and Technology Innovation Cross Project of the Chinese Academy of Sciences (KSCX1-YW-10)
文摘This study aimed to evaluate emerging trends of drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) among 290 former blood donor HIV-1 infected patients in Hubei, China, from 2004 to 2006, all of whom had received anti-HIV-1 therapy. The presence of NRTI- and NNRTI-associated mutations were established by sequencing; genotypic and predicted phenotypic drug resistance were evaluated using HIVdb Program version 5.0.1 (http://hivdb.stanford.edu/ pages/algs/HIVdb.html). Genotypic drug resistance analysis showed significant increases in percentages of patients carrying HIV-1 strains with M41L, T215Y/F, D67N, K103N, G190A/S, Y181C/F or L210W mutations. Of the variants' predicted phenotypic drug resistance, highly significant increases were detected in percentages of patients carrying HIV-1 with high resistance to zidovudine (AZT) or stavudine (D4T) in NRTIs, and to delavirdine (DLV), efavirenz (EFV) or nevirapine (NVP) in NNRTIs; intermediate resistance to abacavir (ABC), AZT, D4T, didanosine (DDI) or tenofovir disoproxil fumarate (TDF) in NRTIs, and to etravirine (ETR) in NNRTIs; and low and potential low resistance to lamivudine (3TC), ABC, emtricitabine (FTC) or TDF in NRTIs, and to ETR in NNRTIs.
基金Supported by the National Natural Science Foundation of China(No.41271205)the PhD Research Startup Foundation of Heibei GEO Univerity(No.BQ201604)
文摘Lake Lop Nur is located in the eastern part of the Tarim Basin in Xinjiang,northwestern China.A 220-cm-long sediment core was collected from the center of the ear-shaped depression forming the basin and dated with AMS^(14)C.Grain size,total organic matter(TOC),total nitrogen(TN),and TOC/TN(C/N)analyses were used to reconstruct climatic conditions from 13.0 to 5.6 cal ka BP.The results showed fi ve main climatic stages.Zone I(13.0–11.3 cal ka BP)was a wet–dry environment,whereas Zone II(11.3–8.9 cal ka BP)consisted of a primarily wet environment.Zone III(8.9–7.7 cal ka BP)was subdivided into Zone IIIa(8.9–8.2 cal ka BP)that indicated lake constriction and dry climate,and Zone IIIb(8.2–7.7 cal ka BP)in which the proxies indicated wet conditions.In Zone IV(7.7–6.6 cal ka BP),the climate presented a bit wet conditions.In Zone V(6.6–5.6 cal ka BP),abundant glauberite is present in the sediment and silt dominates the lithology;these results indicate the lake shrank and the overall climate was dry.Abrupt environmental events were also identifi ed,including six dry events at 11.0,10.5,9.3,8.6,8.2,and 7.6 cal ka BP and one fl ood event from 7.8 to 7.7 cal ka BP in the Early–Middle Holocene.
基金Under the auspices of Knowledge Innovation Programs of Chinese Academy of Sciences (No.KZCX2-YW-341,KZCX2-YW-340)Key Project of Jilin Province Scientific and Technological Development Program (No.20080425)
文摘Research on the optical characteristics of water color constituents in Chagan Lake of Jilin Province,Northeast China was carried out in order to investigate the variability of the spectra absorption parameters as inputs to bio-optical models and remote sensing algorithms for converting observed spectral signals into water quality information.Samples of total particulates,non-algal particles and colored dissolved organic matter (CDOM) were first prepared by quantitative filter technique (QFT) and then absorption coefficients of these color producing agents were determined by spectrophotometry.Spectral characteristics of absorption coefficients by total particulate matter,spectral specific absorption dependency on chlorophyll concentration (Chl-a) of phytoplankton,spectral absorption slopes variation for CDOM and non-algal particles and their corresponding reasons were examined and clarified over five months of 2009 and 2010 in this study.Results suggest that total particulate spectral absorption in Chagan Lake is mainly dominated by non-algal particles in most cases,but phytoplankton could be the dominant contributor when chlorophyll concentration is high (up to 84.48 mg/m3 in autumn 2010).The specific absorption coefficients of phytoplankton particulate (a*ph(λ)) dependency on Chl-a is significantly variable due to relative contributions of package effect and accessory pigments,and the parameters of power function are clearly biased on a long time span.The sources of variability in spectral absorption slopes of CDOM and non-algal particles are mainly attributed to the changing proportions of high molecular weight humic acids and mineral suspended sediments in waters,respectively.
基金Under the auspices of National Natural Science Foundation of China(No.41101295)Shenyang Science and Technology Projects(No.JJ2011-13)
文摘The aquatic ecosystem maybe significantly affected by polycyclic aromatic hydrocarbons(PAHs) released from fresh water sediments. In order to protect biodiversity, the spatial distribution and sources of PAHs in the sediment of Wolong Lake in Northeast China were studied. A total of 17 surface sediment samples were collected and 12 PAHs were analyzed. The results were as follows. The concentration of total PAHs(TPAHs) ranged between 1412.9 μg/kg and 3948.3 μg/kg(dry weight). Indeno [1, 2, 3-c, d] pyrene was the dominant contaminant which accounted for 87%–98% of TPAHs. Diagnostic ratios of PAHs and principal component analysis showed that biomass combustion and vehicle emissions were likely to be the dominant sources of PAHs in the sediment. PAHs can be considered safe in the context of environmental and human health protection, based on the overall toxicity. Individual PAHs were positively correlated with total organic carbons. These results will be helpful to control PAHs and protect the aquatic ecosystem in the lake.
基金supported by the National Natural Science Foundation of China (Grant Nos. 40925012 and 40821091)the Ministry of Science and Technology of China (Grant No. 2007FY110200)the Chinese Academy of Sciences (Grant No. KZCX2-EW-117)
文摘The fluvio-lacustrine sedimentary sequences in the Nihewan Basin, northern China, are important for studying Quaternary land mammal evolution and Paleolithic settlements in the high-latitude temperate East Asia. Here we report new magnetostrati- graphic results that constrain age of the Hougou Paleolithic site in this basin. Magnetite and hematite were identified as carriers of the characteristic remanent magnetizations, with the former being dominant. Magnetic polarity stratigraphy shows that the Hougou sequence recorded the very late Matuyama reverse chron and the Brunhes normal chron. The age of the Hougou Paleolithic site was estimated to be 395 ka based on an averaged rate of sediment accumulation. The combination of our mag- netostratigraphy and previously published chronological data for early Paleolithic or human sites in the high-latitude northern China may document a persistent colonization of the hostile high-latitude areas of the eastern Old World during the mid- die-early Pleistocene.
基金supported by grants from the National Natural Science Foundation of China(81402728,81371865)
文摘Seoul virus(SEOV), which is predominantly carried by Rattus norvegicus, is one of the major causes of hemorrhagic fever with renal syndrome(HFRS) in China. Hubei province, located in the central south of China, has experienced some of the most severe epidemics of HFRS. To investigate the mitochondrial DNA(mt DNA)-based phylogenetics of wild rats in Hubei, and the relationship with SEOV infection, 664 wild rats were captured from five trapping sites in Hubei from2000–2009 and 2014–2015. Using reverse-transcription(RT)-PCR, 41(6.17%) rats were found to be positive for SEOV infection. The SEOV-positive percentage in Yichang was significantly lower than that in other areas. The mt DNA D-loop and cytochrome b(cyt-b) genes of 103 rats were sequenced.Among these animals, 37 were SEOV-positive. The reconstruction of the phylogenetic relationship(based on the complete D-loop and cyt-b sequences) allowed the rats to be categorized into two lineages, R. norvegicus and Rattus nitidus, with the former including the majority of the rats. For both the D-loop and cyt-b genes, 18 haplotypes were identified. The geographic distributions of the different haplotypes were significantly different. There were no significant differences in the SEOVpositive percentages between different haplotypes. There were three sub-lineages for the D-loop,and two for cyt-b. The SEOV-positive percentages for each of the sub-lineages did not significantly differ. This indicates that the SEOV-positive percentage is not related to the mt DNA D-loop or cyt-b haplotype or the sub-lineage of rats from Hubei.
基金supported by the Special Research Fund for the Doctoral Program of Higher Education(Grant No.20126101110020)the National Natural Science Foundation of China(Grant No.41272116)
文摘Santanghu area in northeastern Xinjiang region of Northwest China is an important component of the Central Asian Orogenic Belt(CAOB), in which the dynamic mechanism of Permian magmatism is controversial. In Santanghu area is exposed a thick succession of the Middle Permian basalts, including a small amount of picritic basalts and andesites, known as the Tiaohu Formation. The picritic basalts contain cumulate olivine, and have whole-rock Mg# up to 0.68–0.77; the basalts exhibit porphyritic or doleritic textures, and have relatively low Mg# of 0.41–0.54, typical of evolved magmas. The mafic-ultramafic rocks of the Tiaohu Formation are slightly enriched in Light Rare Earth Elements(LREEs), and exhibit negative Nb and Ti anomalies. They also have high Ti O2 content, and Nb/Y and Zr/Yb ratios greater than those of island arc volcanic rocks. Relatively low initial Sr isotopic ratios and high positive εNd(t) and εHf(t) values argue against contamination by ancient continental crust, and suggest formation of the Tiaohu Formation by partial melting of relatively refractory depleted lithospheric mantle that underwent metasomatism and extraction by fluid from the subducted slab. In addition, up to 38% olivine in picritic basalts indicates high-degree partial melting of lithospheric mantle, and the underlying Lucaogou Formation contains fragments of ultra-alkaline magmatic rocks that originated in the deep mantle. These observations imply wide-spread underplating in Santanghu area, which may have been associated with a mantle plume.
文摘NEW TAOIST LEADERLi Guangfu,previously Vice Chairman of the China Taoist Association(CTA),was elected the new CTA chairman during the association’s national congress in late June.Li was born in central China’s Hubei Province in 1955.He also headed the Taoist Association of Wudang Mountain in Hubei, a hub location for China's Taoist culture.